Noisy Wheels/Brakes and weight and balance


Martin Skiby
 

Good morning group.  My son and I have acquired a Q200 with conventional gear that we are working on.  One of the things that caught me off guard was the amount of noise we are getting now that the brakes are installed.  The wheels and tires are not contacting anything (though it is very tight in the wheel area) but after the install of the brake cylinders man they make a noise.  Now some of that will go away I am sure with normal wear as everything is pretty tight here.  My question is, is this normal to have noise from the wheels with a new set up?


I also have some questions on weight and balance as I see so many variations on the L calculation on the Q2.200.


We are using 14" forward of firewall as the Datum line as in the plans.  That puts the wheels at 38.25 inches as the main weigh points.  From that line I am 172.75 inches to the tail wheel, however I am seeing many calculations using 210+ inches which would be from the Datum line not the forward weighing point that is shown in many other manuals.


So two questions sorry.


Sam Hoskins
 

Mine have always made noise, no matter what I do. Just guessing, but it might be caused by movement of the wheel around the sealed axle bearings. I have tried all sorts of loctite to no avail.

One question, what type of brake mounting system do you have? There have been several over the years.

Sam

On Wed, Nov 2, 2016 at 12:18 PM, mskiby@... [Q-LIST] <Q-LIST@...> wrote:
 

Good morning group.  My son and I have acquired a Q200 with conventional gear that we are working on.  One of the things that caught me off guard was the amount of noise we are getting now that the brakes are installed.  The wheels and tires are not contacting anything (though it is very tight in the wheel area) but after the install of the brake cylinders man they make a noise.  Now some of that will go away I am sure with normal wear as everything is pretty tight here.  My question is, is this normal to have noise from the wheels with a new set up?


I also have some questions on weight and balance as I see so many variations on the L calculation on the Q2.200.


We are using 14" forward of firewall as the Datum line as in the plans.  That puts the wheels at 38.25 inches as the main weigh points.  From that line I am 172.75 inches to the tail wheel, however I am seeing many calculations using 210+ inches which would be from the Datum line not the forward weighing point that is shown in many other manuals.


So two questions sorry.



Paul Fisher
 

mskiby,
Weight and balance is all done using the datum as a reference.  So you should be calculating the tailwheel location from the datum, NOT from the location of the main gear.  When you calculate a center of gravity, it will also be referenced to the datum, not either set of gear.  For reference my main gear are at 36.9 inches and tailwheel is at 211.5 - both aft of the datum.  To calculate moment arms you multiply these numbers by the weights at each wheel and then add them all together.

Also notice that the flight envelope chart published for the Q-200 does not reference a center of gravity.  It uses weight and moment arm (in thousands of inch pounds).  That has confused a number of people as they were calculating their CG location (also aft of datum) and trying to use that in QAC's chart. That will not work!

Weight and balance is really important, so please have someone check your work before you assume it is correct!

Noise from the brakes is not uncommon, but I suppose it depends on what noise you are hearing.  Mine "clacks" as I push it - and it always has.

Hope that helps.

Paul A. Fisher
Q-200, N17PF - 1,600+ hours over 26+ years



On Wed, Nov 2, 2016 at 12:18 PM, mskiby@... [Q-LIST] <Q-LIST@...> wrote:
 

Good morning group.  My son and I have acquired a Q200 with conventional gear that we are working on.  One of the things that caught me off guard was the amount of noise we are getting now that the brakes are installed.  The wheels and tires are not contacting anything (though it is very tight in the wheel area) but after the install of the brake cylinders man they make a noise.  Now some of that will go away I am sure with normal wear as everything is pretty tight here.  My question is, is this normal to have noise from the wheels with a new set up?


I also have some questions on weight and balance as I see so many variations on the L calculation on the Q2.200.


We are using 14" forward of firewall as the Datum line as in the plans.  That puts the wheels at 38.25 inches as the main weigh points.  From that line I am 172.75 inches to the tail wheel, however I am seeing many calculations using 210+ inches which would be from the Datum line not the forward weighing point that is shown in many other manuals.


So two questions sorry.



Paul Fisher
 

Oh, one more thing - make sure you are weighing the plane in flight attitude, not with the tail sitting on the ground.  This will affect both the tail wheel arm distance as well as the weights.

Maybe this is obvious, but I thought I should mention it!

Paul


On Nov 2, 2016 12:38 PM, "Paul Fisher" <rv7a.n18pf@...> wrote:
mskiby,
Weight and balance is all done using the datum as a reference.  So you should be calculating the tailwheel location from the datum, NOT from the location of the main gear.  When you calculate a center of gravity, it will also be referenced to the datum, not either set of gear.  For reference my main gear are at 36.9 inches and tailwheel is at 211.5 - both aft of the datum.  To calculate moment arms you multiply these numbers by the weights at each wheel and then add them all together.

Also notice that the flight envelope chart published for the Q-200 does not reference a center of gravity.  It uses weight and moment arm (in thousands of inch pounds).  That has confused a number of people as they were calculating their CG location (also aft of datum) and trying to use that in QAC's chart. That will not work!

Weight and balance is really important, so please have someone check your work before you assume it is correct!

Noise from the brakes is not uncommon, but I suppose it depends on what noise you are hearing.  Mine "clacks" as I push it - and it always has.

Hope that helps.

Paul A. Fisher
Q-200, N17PF - 1,600+ hours over 26+ years



On Wed, Nov 2, 2016 at 12:18 PM, mskiby@... [Q-LIST] <Q-LIST@...> wrote:
 

Good morning group.  My son and I have acquired a Q200 with conventional gear that we are working on.  One of the things that caught me off guard was the amount of noise we are getting now that the brakes are installed.  The wheels and tires are not contacting anything (though it is very tight in the wheel area) but after the install of the brake cylinders man they make a noise.  Now some of that will go away I am sure with normal wear as everything is pretty tight here.  My question is, is this normal to have noise from the wheels with a new set up?


I also have some questions on weight and balance as I see so many variations on the L calculation on the Q2.200.


We are using 14" forward of firewall as the Datum line as in the plans.  That puts the wheels at 38.25 inches as the main weigh points.  From that line I am 172.75 inches to the tail wheel, however I am seeing many calculations using 210+ inches which would be from the Datum line not the forward weighing point that is shown in many other manuals.


So two questions sorry.



Martin Skiby
 

Thanks Paul,  I completely understand and was confused as most conventional tail wheel craft calculate the tail distance from the main wheel weight point and then use the provide datum in the calculation.

CG = D + (RxL) / W

I see that on the Q2 most folks are using the R from the datum line at 14 Inches in front of the firewall.

I also have a TriQ200 that is flying nicely and am aware of the CG limits, but this tail wheel Q200 has the GU canard so it is much less forgiving.

Thanks for the clarification.  That moves my CG point to 43.77 Aft of Datum which seems farther aft than I was thinking.


Martin Skiby
 

Thanks Sam,  My thoughts also, but wanted to ask the group


Martin Skiby
 

Sorry my response was not complete when I hit send.   We are using the original QAC brackets (which I understand have been improved)

Thanks again for the reply.


Martin Skiby
 

Got it,  Thanks,

What is the normal tail weights folks are seeing?  I put in a pretty large battery to try and prevent adding too much ballast at the tail.


Jay Scheevel
 

Hi Martin,

It that 43.77 is your empty CG, something is not right. The empty CG should be around 40". The loaded CG should be somewhere between 42 and 47" give or take.

Cheers,
Jay Scheevel


Jim Patillo
 

Martin,

Sounds like you bought Mark Summers Q200? He has the only Q200
I know of with a GU canard.  Also we refer to that big assed weight on the tail wheel as an RV lure. 😋  

Did you get the fuel injected electronic ignition 0200 with it? I found that engine for him originally. Are you aware of the crack on the inside of the hub on the Catto Prop?

This plane has been sitting on the ramp in Truckee for over a year.  You should do a good tap test over the wing structures. 

This will be a nice plane for you once you get it back together. 

Regards,
Jim Patillo
N46JP Q200


victor taylor
 

Can anyone tell me if there are mods required to the GU canard for the O-200? Do I need to make it stiffer?

Vic Taylor
Irvington, Alabama


On Thursday, November 3, 2016 5:06 AM, "logistics_engineering@... [Q-LIST]" wrote:


 
Martin,

Sounds like you bought Mark Summers Q200? He has the only Q200
I know of with a GU canard.  Also we refer to that big assed weight on the tail wheel as an RV lure. 😋  

Did you get the fuel injected electronic ignition 0200 with it? I found that engine for him originally. Are you aware of the crack on the inside of the hub on the Catto Prop?

This plane has been sitting on the ramp in Truckee for over a year.  You should do a good tap test over the wing structures. 

This will be a nice plane for you once you get it back together. 

Regards,
Jim Patillo
N46JP Q200




Martin Skiby
 

Jim you are correct.  This was Mark's Q200 and what a nice plane it is.  It was outside and inside at Truckee and actually shows little signs of weather at all.  Even the canopy cleaned up very nicely.  Yes we have tap tested the wings very well and are confident that they are good.  Yes I was able to meet with Mark and get the fuel injected motor and systems.

We are doing quite a bit of checking and safety oversight on the plane and so far we have been very pleased.  Mark did an awesome job on this plane and I just could not stand to see it sitting on the ramp up there.  There is a long story of what we had to do to convince the airport to let us acquire it, and we even got Mark to say OK after we talked and he was convinced we knew a few things about the Q2.

I increased the size of the battery considerably and it appears that the RV lure may get to stay in the tackle box!!! 

Thanks for reaching out and sorry I could not take you call last evening.  I will call you today.


Martin Skiby
 

Vic,

I am not aware of any required changes to use the GU canard with an 0200, however the CG range is much more critical for the GU and you MUSTS use the VG's on it.

Also I understand that they do not like rough terrain.  The Q200 I have with a GU was flown 500 hrs before it was removed from service so I am confident it can be done safely in the correct environment.



Calvin Thorne
 

I do not speak up on this group often but I have a GU canard with the conventional wheels.  During my rebuild I had played with the wheel/brake mating quite a lot.  The wheel is positioned by the through axle and my Airheart brake system is mounted to the inner wall of the wheel pant.  I had to use various numbers of washers on the upper and lower brake mounts to get the wheel to track without dragging.  My Q2 (Revmaster) makes almost no noise when rolling except for very light rubbing of the brake puck on the disc.   If you want I can email you my line drawing of my wheel and waher setup, each wheel is requires different waher numbers.

Q2 (Revmaster) C-GMBK 1800 hrs

Calvin Thorne

Cochrane Alberta

Web:  www.calvinthorne.blogspot.ca


Jim Patillo
 

I agree with Calvin. My Q200 doesn't make any noise either when pushing it around. I have the "LaRue" brake mod. When I set it up I also used washers behind the plates to true up the puck/disc. It just takes a little time to get it right. 

Jim Patillo
N46JP Q200


Martin Skiby
 

Thanks group.  I think we have some more playing around to do with spacing etc...


MATT HUGHES
 

This is not related to the topic...sorry in advance.
Calvin, I'm flying a q1 out of olds/didsbury. I live in Cochrane, would like too see your bird.