Forward Canopy geometry
Hi Vern,
toggle quoted messageShow quoted text
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area. Cheers, Jay
On Mar 21, 2021, at 5:54 PM, smeshno1@... wrote:
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|
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic
fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks!
The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now
with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available
( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight
instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for
me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Sunday, March 21, 2021 8:30 PM To: main@q-list.groups.io <main@q-list.groups.io> Subject: [Q-List] Forward Canopy geometry Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option
of modifying the transition area.
Cheers,
Jay
On Mar 21, 2021, at 5:54 PM, smeshno1@... wrote:
|
|
Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Sent: Monday, March 22, 2021 9:01 AM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
|
|
Excellent thought-out method, Jay. In a roll over you'd be without worry. I also see not much "sky" is blanked out for the needs of visual separation. I like your split design a lot. 👍
That experience scared me enough to consider that Certificated ownership was (is) hampered by not being allowed to innovate legally! Even if it made logical sense to do mods. That being said; I owned and perfected N1100Y (1962 B model 150) as much as
I could for over two decades.
My thoughts on the fuel eject is based on pressurizing the header tank to purposely blow a fuel jettison "fuse" just ahead of a jettison vent downstream from the
main tank (at the lower "keel" and just forward of the shell joint seam); thereby both tanks are made empty in short order. Similar to how the pressure system works on some biz jets (Falcon 20 for one). For redundant seal protection, a manual valve is in front
of the "fuse". Of course the dump handle is brite red, positive lockout, and placard indicated for it's use.
Once the decision is made to offload the benzine, there is for sure a dead stick landing on the way; but by that time PIC already has the chosen off field (or
possibly with luck, an airport..) parking place.
Most of you guys know that I was very involved in the Engineering side of the 777 and 747 flammability
program (affected all airliner new build fleets in all Nations from 2004 and on, not just America) and from that I learned a lot about what can be done under our cowling as well.
Not much weight or vast amounts of money to upgrade..and all of the mods are well known and tested to be effective. Just having the mental margin that you'd have
a very good chance at surviving an in flight fire makes it worth the time and cost.
There is no such thing as flight safety...but there is such a thing as risk management.
As pilots, all of us (should) have training to back us up but if the airplane doesn't give us a chance to use it we would still end up taking a dirt nap needlessly.
After many millions in testing at the lazy B we made the grade by using Conolite and stainless or titanium details at all "penetrations". Also by capturing the
joints (such as the IML of the cowling to the added Conolite firewall buffer) with cheap and lite fiberglass single adhesive tape (use 2" or 3" wide) under the panel attach fasteners, the structural elements are buffered from the heat once the tape adhesive
gives up (about .5 seconds!). The fiberglass tape then "pillows" and an air pocket develops..so effective insulation happens at the joints automatically.
Using stainless steel screws and 1/2" long standoff tubes the thin Conolite sheet leaves a 1/2" air pocket from the original .025" thick stainless firewall,
same thing happens with the Conolite, the resin boils out quickly and the fiberglass cloth remaining becomes effective flame block and insulation automatically. Because the fiberglass tape is on the inside of the cowling joints the fire cannot escape the aft
cowling area junction at the fuselage.
Discharge a small Kidde foam fire extinguisher through nozzles located under the cowling and an oil fire no longer becomes a bad story for General Aviation aircraft
on the 6 o'clock news. I have one in my Capella..it doesn't weigh much at all.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Monday, March 22, 2021 11:12 AM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Forward Canopy geometry Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
|
|
Hi Vern,
Yes, I preserved almost the entire area of the original plexiglass canopy, by sliding it “around the sphere” of the original glass shape. The following two videos are time lapse compression of my fabrication of the doors and overhead beam/console.
Yours sounds like a good plan for gas tank evacuation, provided it does not blowout the edge seams of the tanks.
You should query Jerry Marstall for his solution to automatic cockpit fire suppression, adapted from the motor car racing world. It looks like it would be very effective and is essentially automatic. I will allow him to elaborate further.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Sent: Monday, March 22, 2021 1:50 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry
Excellent thought-out method, Jay. In a roll over you'd be without worry. I also see not much "sky" is blanked out for the needs of visual separation. I like your split design a lot. 👍
That experience scared me enough to consider that Certificated ownership was (is) hampered by not being allowed to innovate legally! Even if it made logical sense to do mods. That being said; I owned and perfected N1100Y (1962 B model 150) as much as I could for over two decades.
My thoughts on the fuel eject is based on pressurizing the header tank to purposely blow a fuel jettison "fuse" just ahead of a jettison vent downstream from the main tank (at the lower "keel" and just forward of the shell joint seam); thereby both tanks are made empty in short order. Similar to how the pressure system works on some biz jets (Falcon 20 for one). For redundant seal protection, a manual valve is in front of the "fuse". Of course the dump handle is brite red, positive lockout, and placard indicated for it's use.
Once the decision is made to offload the benzine, there is for sure a dead stick landing on the way; but by that time PIC already has the chosen off field (or possibly with luck, an airport..) parking place.
Most of you guys know that I was very involved in the Engineering side of the 777 and 747 flammability program (affected all airliner new build fleets in all Nations from 2004 and on, not just America) and from that I learned a lot about what can be done under our cowling as well.
Not much weight or vast amounts of money to upgrade..and all of the mods are well known and tested to be effective. Just having the mental margin that you'd have a very good chance at surviving an in flight fire makes it worth the time and cost.
There is no such thing as flight safety...but there is such a thing as risk management. As pilots, all of us (should) have training to back us up but if the airplane doesn't give us a chance to use it we would still end up taking a dirt nap needlessly.
After many millions in testing at the lazy B we made the grade by using Conolite and stainless or titanium details at all "penetrations". Also by capturing the joints (such as the IML of the cowling to the added Conolite firewall buffer) with cheap and lite fiberglass single adhesive tape (use 2" or 3" wide) under the panel attach fasteners, the structural elements are buffered from the heat once the tape adhesive gives up (about .5 seconds!). The fiberglass tape then "pillows" and an air pocket develops..so effective insulation happens at the joints automatically.
Using stainless steel screws and 1/2" long standoff tubes the thin Conolite sheet leaves a 1/2" air pocket from the original .025" thick stainless firewall, same thing happens with the Conolite, the resin boils out quickly and the fiberglass cloth remaining becomes effective flame block and insulation automatically. Because the fiberglass tape is on the inside of the cowling joints the fire cannot escape the aft cowling area junction at the fuselage.
Discharge a small Kidde foam fire extinguisher through nozzles located under the cowling and an oil fire no longer becomes a bad story for General Aviation aircraft on the 6 o'clock news. I have one in my Capella..it doesn't weigh much at all.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
|
|
Jay, That is a great picture. I notice you have closing plates at the end of your elevators, is
your fuel tank behind that area or is there a void behind ? Br Rich T.
On 22/03/2021 16:12, Jay Scheevel
wrote:
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|
Lot of good design and methods comes from the racing world. I look forward to what Jerry offers. I am grateful for your efforts and on another Blog dealing with aviation I suggest recording
the build on thumb drive for the DAR and more especially a record for ones own memory support. Upload and store video is a boost to the Airworthiness sign off and later builders as myself. Also good was advising on overseas sign off. The Commonwealth Nations
are particularly difficult. Delt with that a few times in my aircraft factory life, so I don't envy builders of Experimental in those parts of the world.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Monday, March 22, 2021 3:17 PM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Forward Canopy geometry Hi Vern,
Yes, I preserved almost the entire area of the original plexiglass canopy, by sliding it “around the sphere” of the original glass shape. The following two videos are time lapse compression of my fabrication of the doors and overhead beam/console.
Yours sounds like a good plan for gas tank evacuation, provided it does not blowout the edge seams of the tanks.
You should query Jerry Marstall for his solution to automatic cockpit fire suppression, adapted from the motor car racing world. It looks like it would be very effective and is essentially automatic. I will allow him to elaborate further.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Excellent thought-out method, Jay. In a roll over you'd be without worry. I also see not much "sky" is blanked out for the needs of visual separation. I like your split design a lot. 👍
That experience scared me enough to consider that Certificated ownership was (is) hampered by not being allowed to innovate legally! Even if it made logical sense to do mods. That being said; I owned and perfected N1100Y (1962 B model 150) as much as I could for over two decades.
My thoughts on the fuel eject is based on pressurizing the header tank to purposely blow a fuel jettison "fuse" just ahead of a jettison vent downstream from the main tank (at the lower "keel" and just forward of the shell joint seam); thereby both tanks are made empty in short order. Similar to how the pressure system works on some biz jets (Falcon 20 for one). For redundant seal protection, a manual valve is in front of the "fuse". Of course the dump handle is brite red, positive lockout, and placard indicated for it's use.
Once the decision is made to offload the benzine, there is for sure a dead stick landing on the way; but by that time PIC already has the chosen off field (or possibly with luck, an airport..) parking place.
Most of you guys know that I was very involved in the Engineering side of the 777 and 747 flammability program (affected all airliner new build fleets in all Nations from 2004 and on, not just America) and from that I learned a lot about what can be done under our cowling as well.
Not much weight or vast amounts of money to upgrade..and all of the mods are well known and tested to be effective. Just having the mental margin that you'd have a very good chance at surviving an in flight fire makes it worth the time and cost.
There is no such thing as flight safety...but there is such a thing as risk management. As pilots, all of us (should) have training to back us up but if the airplane doesn't give us a chance to use it we would still end up taking a dirt nap needlessly.
After many millions in testing at the lazy B we made the grade by using Conolite and stainless or titanium details at all "penetrations". Also by capturing the joints (such as the IML of the cowling to the added Conolite firewall buffer) with cheap and lite fiberglass single adhesive tape (use 2" or 3" wide) under the panel attach fasteners, the structural elements are buffered from the heat once the tape adhesive gives up (about .5 seconds!). The fiberglass tape then "pillows" and an air pocket develops..so effective insulation happens at the joints automatically.
Using stainless steel screws and 1/2" long standoff tubes the thin Conolite sheet leaves a 1/2" air pocket from the original .025" thick stainless firewall, same thing happens with the Conolite, the resin boils out quickly and the fiberglass cloth remaining becomes effective flame block and insulation automatically. Because the fiberglass tape is on the inside of the cowling joints the fire cannot escape the aft cowling area junction at the fuselage.
Discharge a small Kidde foam fire extinguisher through nozzles located under the cowling and an oil fire no longer becomes a bad story for General Aviation aircraft on the 6 o'clock news. I have one in my Capella..it doesn't weigh much at all.
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io>
On Behalf Of smeshno1@...
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
|
|
Hi Richard,
That is a hollow strake. I copied it after shapes I had seen on corporate jets. I figured good enough for them, good enough for me. That plate comes off to slide my elevator inboard for removal. The left strake also houses my downward looking precision radar altimeter. Main tank is per plans, so is not impacted by these strakes. The construction details are shown in two time lapse videos: https://youtu.be/mDo6t2kM5VM and https://youtu.be/gKGtZ4oxDfo
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Richard Thomson
Sent: Monday, March 22, 2021 4:25 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry
Jay, That is a great picture. I notice you have closing plates at the end of your elevators, is your fuel tank behind that area or is there a void behind ? Br Rich T.
On 22/03/2021 16:12, Jay Scheevel wrote:
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Thanks Jay , I will have a look. FN has the closing plates as well, always wondered how close
the screw holes were to the tank wall. Precision radar eh, have you got Doppler as well ?? :-) Br Rich.
On 22/03/2021 23:39, Jay Scheevel
wrote:
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Sorry Richard, I misspoke. Should have said lidar altimeter. Very useful on landing. Calls out AGL to me as I round out and right down to touchdown. Kind of like having Buzz Aldrin sitting next to me in the LEM :-)
toggle quoted messageShow quoted text
Cheers, Jay
On Mar 23, 2021, at 4:39 AM, Richard Thomson <richard@...> wrote:
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Great Idea, thats even better than PRA, and with talk down thrown in at a fraction of the price. Its a wonder there isnt a Q200 in Florida with a similar set up. :-) Lots of energy expended in your videos, made me tired just
watching. Thanks Jay. Br Rich.
On 23/03/2021 12:05, Jay Scheevel
wrote:
Sorry Richard, I misspoke. Should have said lidar altimeter. Very useful on landing. Calls out AGL to me as I round out and right down to touchdown. Kind of like having Buzz Aldrin sitting next to me in the LEM :-)
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Jerry Marstall <jnmarstall@...>
The next time I pull the cowling, I’ll take some pictures of the race car fire suppression system. Unless I find pictures sooner. Jerry
From: main@Q-List.groups.io [mailto:main@Q-List.groups.io] On Behalf Of smeshno1@...
Sent: Monday, March 22, 2021 7:03 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry
Lot of good design and methods comes from the racing world. I look forward to what Jerry offers. I am grateful for your efforts and on another Blog dealing with aviation I suggest recording the build on thumb drive for the DAR and more especially a record for ones own memory support. Upload and store video is a boost to the Airworthiness sign off and later builders as myself. Also good was advising on overseas sign off. The Commonwealth Nations are particularly difficult. Delt with that a few times in my aircraft factory life, so I don't envy builders of Experimental in those parts of the world.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
Yes, I preserved almost the entire area of the original plexiglass canopy, by sliding it “around the sphere” of the original glass shape. The following two videos are time lapse compression of my fabrication of the doors and overhead beam/console.
Yours sounds like a good plan for gas tank evacuation, provided it does not blowout the edge seams of the tanks.
You should query Jerry Marstall for his solution to automatic cockpit fire suppression, adapted from the motor car racing world. It looks like it would be very effective and is essentially automatic. I will allow him to elaborate further.
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Excellent thought-out method, Jay. In a roll over you'd be without worry. I also see not much "sky" is blanked out for the needs of visual separation. I like your split design a lot. 👍
That experience scared me enough to consider that Certificated ownership was (is) hampered by not being allowed to innovate legally! Even if it made logical sense to do mods. That being said; I owned and perfected N1100Y (1962 B model 150) as much as I could for over two decades.
My thoughts on the fuel eject is based on pressurizing the header tank to purposely blow a fuel jettison "fuse" just ahead of a jettison vent downstream from the main tank (at the lower "keel" and just forward of the shell joint seam); thereby both tanks are made empty in short order. Similar to how the pressure system works on some biz jets (Falcon 20 for one). For redundant seal protection, a manual valve is in front of the "fuse". Of course the dump handle is brite red, positive lockout, and placard indicated for it's use.
Once the decision is made to offload the benzine, there is for sure a dead stick landing on the way; but by that time PIC already has the chosen off field (or possibly with luck, an airport..) parking place.
Most of you guys know that I was very involved in the Engineering side of the 777 and 747 flammability program (affected all airliner new build fleets in all Nations from 2004 and on, not just America) and from that I learned a lot about what can be done under our cowling as well.
Not much weight or vast amounts of money to upgrade..and all of the mods are well known and tested to be effective. Just having the mental margin that you'd have a very good chance at surviving an in flight fire makes it worth the time and cost.
There is no such thing as flight safety...but there is such a thing as risk management. As pilots, all of us (should) have training to back us up but if the airplane doesn't give us a chance to use it we would still end up taking a dirt nap needlessly.
After many millions in testing at the lazy B we made the grade by using Conolite and stainless or titanium details at all "penetrations". Also by capturing the joints (such as the IML of the cowling to the added Conolite firewall buffer) with cheap and lite fiberglass single adhesive tape (use 2" or 3" wide) under the panel attach fasteners, the structural elements are buffered from the heat once the tape adhesive gives up (about .5 seconds!). The fiberglass tape then "pillows" and an air pocket develops..so effective insulation happens at the joints automatically.
Using stainless steel screws and 1/2" long standoff tubes the thin Conolite sheet leaves a 1/2" air pocket from the original .025" thick stainless firewall, same thing happens with the Conolite, the resin boils out quickly and the fiberglass cloth remaining becomes effective flame block and insulation automatically. Because the fiberglass tape is on the inside of the cowling joints the fire cannot escape the aft cowling area junction at the fuselage.
Discharge a small Kidde foam fire extinguisher through nozzles located under the cowling and an oil fire no longer becomes a bad story for General Aviation aircraft on the 6 o'clock news. I have one in my Capella..it doesn't weigh much at all.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
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Gud deal! When you can Jerry.. I am generating the build manual...same as my previous life in aviation
where this was part of my job. Build plans based on the projected mission goal of the aircraft...in this case
the revisions to the original RAF manual.
I have plenty of documents to back up with also. Every newsletter from day one, paper and CD. I have the
steel spring MKII sketches (not intended to go that way), Dragonfly items as well. Just about every factor
other than individual revisions made custom by builders now aviating.
The general status of the airframe is all the fuselage bulkheads are completed (by vacuum infusion, my preferred
method). The canopy was fitted by previous builder..the
three other shells are untouched. Both flying surfaces
are
built..ailerons and elevators still to do. Vertical and Rudder not
fabricated yet. I will be fabricating my own cowling
from scratch.
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jerry Marstall <jnmarstall@...>
Sent: Tuesday, March 23, 2021 8:16 AM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Forward Canopy geometry The next time I pull the cowling, I’ll take some pictures of the race car fire suppression system. Unless I find pictures sooner. Jerry
From: main@Q-List.groups.io [mailto:main@Q-List.groups.io]
On Behalf Of smeshno1@...
Lot of good design and methods comes from the racing world. I look forward to what Jerry offers. I am grateful for your efforts and on another Blog dealing with aviation I suggest recording the build on thumb drive for the DAR and more especially a record for ones own memory support. Upload and store video is a boost to the Airworthiness sign off and later builders as myself. Also good was advising on overseas sign off. The Commonwealth Nations are particularly difficult. Delt with that a few times in my aircraft factory life, so I don't envy builders of Experimental in those parts of the world.
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
Yes, I preserved almost the entire area of the original plexiglass canopy, by sliding it “around the sphere” of the original glass shape. The following two videos are time lapse compression of my fabrication of the doors and overhead beam/console.
Yours sounds like a good plan for gas tank evacuation, provided it does not blowout the edge seams of the tanks.
You should query Jerry Marstall for his solution to automatic cockpit fire suppression, adapted from the motor car racing world. It looks like it would be very effective and is essentially automatic. I will allow him to elaborate further.
Cheers, Jay
From:
main@Q-List.groups.io <main@Q-List.groups.io>
On Behalf Of smeshno1@...
Excellent thought-out method, Jay. In a roll over you'd be without worry. I also see not much "sky" is blanked out for the needs of visual separation. I like your split design a lot. 👍
That experience scared me enough to consider that Certificated ownership was (is) hampered by not being allowed to innovate legally! Even if it made logical sense to do mods. That being said; I owned and perfected N1100Y (1962 B model 150) as much as I could for over two decades.
My thoughts on the fuel eject is based on pressurizing the header tank to purposely blow a fuel jettison "fuse" just ahead of a jettison vent downstream from the main tank (at the lower "keel" and just forward of the shell joint seam); thereby both tanks are made empty in short order. Similar to how the pressure system works on some biz jets (Falcon 20 for one). For redundant seal protection, a manual valve is in front of the "fuse". Of course the dump handle is brite red, positive lockout, and placard indicated for it's use.
Once the decision is made to offload the benzine, there is for sure a dead stick landing on the way; but by that time PIC already has the chosen off field (or possibly with luck, an airport..) parking place.
Most of you guys know that I was very involved in the Engineering side of the 777 and 747 flammability program (affected all airliner new build fleets in all Nations from 2004 and on, not just America) and from that I learned a lot about what can be done under our cowling as well.
Not much weight or vast amounts of money to upgrade..and all of the mods are well known and tested to be effective. Just having the mental margin that you'd have a very good chance at surviving an in flight fire makes it worth the time and cost.
There is no such thing as flight safety...but there is such a thing as risk management. As pilots, all of us (should) have training to back us up but if the airplane doesn't give us a chance to use it we would still end up taking a dirt nap needlessly.
After many millions in testing at the lazy B we made the grade by using Conolite and stainless or titanium details at all "penetrations". Also by capturing the joints (such as the IML of the cowling to the added Conolite firewall buffer) with cheap and lite fiberglass single adhesive tape (use 2" or 3" wide) under the panel attach fasteners, the structural elements are buffered from the heat once the tape adhesive gives up (about .5 seconds!). The fiberglass tape then "pillows" and an air pocket develops..so effective insulation happens at the joints automatically.
Using stainless steel screws and 1/2" long standoff tubes the thin Conolite sheet leaves a 1/2" air pocket from the original .025" thick stainless firewall, same thing happens with the Conolite, the resin boils out quickly and the fiberglass cloth remaining becomes effective flame block and insulation automatically. Because the fiberglass tape is on the inside of the cowling joints the fire cannot escape the aft cowling area junction at the fuselage.
Discharge a small Kidde foam fire extinguisher through nozzles located under the cowling and an oil fire no longer becomes a bad story for General Aviation aircraft on the 6 o'clock news. I have one in my Capella..it doesn't weigh much at all.
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Great story, Vern.
The fuel dump idea had occurred to me when I was building (and probably several others on this list), but I could not find a way to make it happen expeditiously, especially from the header tank, so I did not do that. I did make sure that if the tanks stay intact on a roll over, they will not dribble fuel all over me, but there is no guarantee that everything stays intact in such a circumstance that flips you over. Exiting the aircraft is a bit easier in my configuration, as the overhead console is very stiff (I have had two people sitting on it without any deflection, so will serve to keep the cockpit from being crushed. If you are inverted, once you push the door over center, it stays full open. Here is a photo of my configuration (taken immediately after my first flight).
Cheers, Jay
From:
main@Q-List.groups.io <main@Q-List.groups.io>
On Behalf Of smeshno1@...
Ala.. Spitfire or perhaps P-51? The addition of a carbon hoop "roll bar" already was in my build plan. I would like to see your split canopy method chosen. If in case of an unexpected Frankenbird "inverted parking position" I also planned on a simplistic fuel purge to be used prior to emergency touchdown. Offloading all the fuel possible would offer time to exit before a bar b cue event.
I've personally "enjoyed" an inflight fire. I had just soloed also. Had about 6.5 hours in my student pilot log book.
The transponder was removed for the inspection (the 152 was IFR equipped) and the remover (my instructor at the time) unknown to me failed to tie back the transponder co-axial cable behind the instrument panel.
Mr. Murphy stepped in on my solo flight (as he is quite apt to do in aviation) after the removal of the avionic unit, and the loose co-axial shielded ground cable welded itself to the positive buss bar behind the instrument panel. Sparks ..LOTs of sparks! The carpet was set afire...so I had the rather unpleasent experience of the WW1 "hot foot" and the single fuel selector valve near the flames in THICK acrid smoke. Opened the window and hit the main "off" electrical..but still had flaming carpet only now with more oxygen on hand!! Not a good situation.
Altitude was about 1500 ft since I had just departed runway 18 so I was flying over a dense metropolitan part of North Little Rock at the time. I had my E6B available ( 1980 Jeppesen..metal and analog..no batteries required) and proceeded to stamp out the flaming carpet. Obviously, I made it back to the field. On roll out I un-buckled,exited the aircraft at the point of a fast walking speed, and let her roll on.
Walked in shaken but otherwise ok to the FBO and promptly called the local FSDO office and the investigation later ended up being rather unfortunate for my flight instructor since he was also the aircraft owner. The co-axial was melted all the way back to the antenna on the belly...close to the lowest point fuel drain. Too close according to FAR's.
So some of the ideas I intend to add are perhaps just stem from logic. Fuel dumps on Biz jets and Airliners are standard industry items for good reason..and for me this part of aviation systems safety is something I learned at 6 hours in my pilots log book. Should be included on my homebuilt Experimentals. Cessna and Piper don't seem to think the same as I do on this topic.
As the comedian Mr. Richard Prior once said "Fire is Inspirational!" I'll vouch that it is indeed.
The canopy drag fairing and addition of the hoop are going in the build also. To emergency exit I plan on cutting the canopy from inside.
Any photos of your canopy mod?
Vern
From:
main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Hi Vern,
I built a transition like you describe into my forward canopy. It was partially to cut that draggy transition you describe and partially to facilitate my split canopy. The forward portion of my canopy is permanently mounted, so that gave me the option of modifying the transition area.
Cheers, Jay
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Chris Walterson
Any one have any interesting tricks for positioning the airplane to prime and paint. I am thinking of trying to partially stand the fuselage up to be able to access the bottom, and make some type of rotisserie for the tail section. Any idea? Chris
-- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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I made an appliance that attached to the engine mount and it allowed me to stand it up or put it right side up or upside down (with help of friends) depending on what I wanted to do. I can send pictures if you want.
toggle quoted messageShow quoted text
Cheers, Jay
-----Original Message-----
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Dorothea Keats Sent: Tuesday, March 23, 2021 2:27 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry Any one have any interesting tricks for positioning the airplane to prime and paint. I am thinking of trying to partially stand the fuselage up to be able to access the bottom, and make some type of rotisserie for the tail section. Any idea? Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Make a Tic Tac Toe 2x4 frame and attach to the 4 motor mounts. You can set the fuselage on the nose or rotate on 45degree increments.
Jim
N46JP Q200
Sent from Outer Space
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Tuesday, March 23, 2021 2:04:27 PM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Forward Canopy geometry I made an appliance that attached to the engine mount and it allowed me to stand it up or put it right side up or upside down (with help of friends) depending on what I wanted to do. I can send pictures if you want.
Cheers, Jay -----Original Message----- From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Dorothea Keats Sent: Tuesday, March 23, 2021 2:27 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Forward Canopy geometry Any one have any interesting tricks for positioning the airplane to prime and paint. I am thinking of trying to partially stand the fuselage up to be able to access the bottom, and make some type of rotisserie for the tail section. Any idea? Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Mike Steinsland
I've been kicking around an idea because I too have to flip this puppy soon Attached a really really quick sketch of something I've been mulling over using some 3/4 ply I have laying around Make it out of plywood with a flat spot on the top and bottom Have the top tall enough to give you the right height when flipped over I figure a couple of guys could flip it up on its nose and continue on to it's back. Possibly put some locking castor wheels on it to move it around
On Tue., Mar. 23, 2021, 5:30 p.m. Jim Patillo, <Logistics_engineering@...> wrote:
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With all the talk about fuel dumping, tank integrity, and motorsports, I'm very surprised I have not seen or heard of fuel cells or fuel bladders being used in homebuilt composite aircraft.
All of my race cars have used fuel cells with flexible and puncture resistant bladders. Both of the companies I buy from started out in the aircraft industry and I think still serve that industry. Here's a link to a common supplier of high end (expensive) onboard fire suppression systems used in amateur and professional car racing. https://www.lifeline-fire.co.uk/
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The airframe needs to be as light as possible. The foam filled fuel tanks would take away a bit of fuel volume wouldn’t it?
toggle quoted messageShow quoted text
Bruce
On Mar 23, 2021, at 6:18 PM, Anthony P <solarant@...> wrote:
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Anthony P
You don't have to use foam.
I have a mid-tear 10 gal. cell and the bladder is 3 lbs. They have higher priced and lighter bladder materials. 3 lbs doesn't seem to be too much of a sacrifice for the safety, especially if the alternative is a rapid dump/eject system.
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