static thrust test report

Jay Scheevel

Hi All,

I have been doing some static thrust testing. I strapped my main gear to two steel stakes, and measured thrust using an electronic livestock hoist scale in line with the strap. I did a stepped test and recorded the scale readings with a video camera for the entire experiment. I did the test in a tie down area with  thick grass, where I measured an actual 75 pounds of “break-away” pull to move the plane by hand with a strap on the nose gear leg. Here is graph of the RPM history (green) for the experiment. Blue is my header tank fuel level. Time in minutes at the bottom of the graph

I am using a “generic” thrust computation equation to compute the expected thrust from my prop (54X62) for comparison to my actual measurements. My max static RPM is 2760 RPM, at a density altitude of 6000’ when I did these tests. After adding the 75 pound “break away” into the measured thrust, I get 295 pounds of thrust at 2760 static RPM.  Plotting thrust measurements for  all RPM steps in the experiment I get the blue curve in the right hand graph below. The orange curve is the computed static thrust vs. RPM (zero forward velocity) using the equation. A very good match between computed and measured.  The left hand graph (single blue curve) is CAS as a function of ground roll, factoring in 50 pounds of landing gear friction up to 80 MPH (take off). This calculation includes airframe and induced drag increasing with speed as well as airspeed corrections applied to the calculated thrust.

The curve shows that I will require about 1300 feet of ground roll at 1300 GW to reach 80 mph CAS and then should achieve 160 CAS about 3 miles down range after takeoff if at full throttle and neglecting climb. At 1000 GW about 1000 feet of ground roll should be required to reach 80 mph CAS.

The Jabiru engine manual lists recommended static RPM range of 2600-2800 for my engine. I am in the upper end of that range, so I feel pretty good about the prop that I have for test flying.

Oh, by the way, I’m getting better with taxiing now. Partially because of new master cylinders and partially because I am learning technique. Still going slow, but getting better and faster.

Cheers,

Jay Scheevel, Tri-Q, prepping aircraft and pilot for flight.

Flight Report... heavy

Mike Dwyer

I just flew a friend that had put on some weight.  275lbs now.

The temp was 85F and about 85% humidity.
My normal flying is done with the wife and gross is around 1000lb.
At 1136 lbs the Q200 flew like a completely different airplane!  Very pitch sensitive.  Very slow acceleration.  On landing I carried 10K more airspeed and that worked out perfectly.  Only problem is my landing roll out was around 5000' vs my normal 1600'.  I was easy on the brakes but still!

So Bottom line: at or below 1000lb the Q200 is an awesome airplane.  When you push it to 1100+ I don't like it at all.  This could account for all the differences in handling and pilot reports we've read all these years!  Keep it light!  Check out my Youtube page linked below for video of the takeoff and landing.

PS, my low/no carb diet for 4 months = 14lb weight loss (160 now) and a much lower blood sugar number.  Drop those pounds and keep your rate of climb up!

Mike Dwyer
Q200 N3QP

Q200 Website: http://goo.gl/V8IrJF

FW: Re: RFI and/or RMI I don't know the difference

Rick Hole

To answer the question RFI / EMI.  Electromagnetic interference is the broader category which include Radio Frequency Interference.  When I wrote RFI it was because the interference is known to be caused by a radio frequency source.  EMI would also have been acceptable.

Rick Hole

Re: RFI and/or RMI I don't know the difference

quickieaircraft

Glad to hear it was a success!

Now we'll all be adding ferrite beads.  RF can be a challenge with composite planes.

Best,
IF
TriQ200 ~85 hrs

RFI and/or RMI I don't know the difference

Bruce Crain

Rick Hole thank you for your help! It worked perfectly with respect to the ferrite beads on the antenna end of the RG400. In the past when I would key the mic the fuel guage needle would peg out. Now it is solid as a rock. I did ask Bevan Rabel of Wichita if I needed the ferrite beads on the TXP coax and they said that I did not.

The auto pilot is working wonderfully well at any frequency. Straight as a string. I did put new RG400 coax to both the comm radio and the TXP plus rerouting the coax from the radio past the autopilot servo made all the difference in the world for the autopilot. Everything is fixed on the TriQ 200 and working top notch! Nothing to do but aviate!

Bruce Crain
N96BJ
____________________________________________________________
We Say Goodbye To Lara Spencer
risingstarnewspaper.com
http://thirdpartyoffers.juno.com/TGL3131/5b1f42f2c95f342f215ddst02vuc

Re: Comm/autopilot problems

Rick Hole

Transponders are in the 1 GHz (microwave) range.  Whether the same ferrite beads will be effective there I can’t predict.  It wouldn’t hurt to try it.  My guess would be since the transponder is a fixed frequency device, and in general we use commercial antennas for them, so it is likely that the impedance match is quite good and the ferrites may not improve it much.  If you home-brew the TXP antenna all bets are off considering a small fraction of an inch in length would change the center frequency considerably.  SWR meters for microwave may be available, at a price.

You might take a look at the ground for you’re A/P servo.  Since you are seeing RFI you may need a low impedance ground.  That means a heavier wire or better yet braid strap.  The ½” copper foil tape commonly used for antennas should work fine.

Rick Hole

Re: Comm/autopilot problems

Bruce Crain

Comm/autopilot problems

Rick Hole

Bruce, you will remember me from my years at Velocity. I made and installed
countless antennas before retiring. RG-400 is indeed superior and all but
eliminates RF radiating from the center conductor through the outer layers
of shielding. There is another issue at play however. If the antenna is
not a perfect impedance match for the transmitter/coax system some RF will
return on the outside of the shield. We measure that as Standing Wave Ratio
(VSWR). The VHF Com band is wide and no antenna will have a perfect match
from the low to high end. You are likely seeing less interference with your
autopilot in the frequency range where your antenna is best matched (lowest
SWR).
I always threaded the coax through three ferrite donuts as close as possible
to the antenna connection, leaving an air gap between each. These act as RF
chokes and prevent the RF from travelling back on the coax. If you don't
have these installed already I recommend adding them to yours and any future
VHF antennas.
I don't have the specs on these donuts any more, but I think a call to
Velocity parts might provide a source.

Rick Hole

Comm/autopilot problems

Bruce Crain

For you builders and flyers hopefully this will help you avoid problems with respect to RMI or RFI even when you think the RG400 coax is bullet proof. My comm coax is run down the right side of the fuz and nothing else is run down that side with it. The only place it came close to is where the problem began which is the autopilot servo. In the past if I had a problem with a certain freq (I now understand it is the higher freqs above 127.0 on the comm freqs that were giving me the problems) I would just ask Center or approach if they had another freq as this one is messing with my autopilot.

I did some trouble shooting with the comm and autopilot interaction with respect to the higher frequencies on the radio. Particularly on Wichita approach. The frequency 134.85 (Wichita approach) would bank the Q left on this frequency. I did some testing and it seemed that anything above 127.0 comm frequency would make the autopilot turn and bank. I took a look in the tail cone and noticed 2 holes in the bulkhead before the split line in the fuz. The hole I was using to run the RG400 comm coax through was only about 4" away from the autopilot servo. So I drilled another hole about 10 to 12 inches away from the autopilot and re-ran the RG400 to the comm antenna in the tail cone. Before I flew I tested the autopilot with the comm set at the offending 134.85 freq. It seemed solid!

Then I flew up toward Wichita and tuned in their freq (134.85) and talked with them and the autopilot stayed solid as a rock. Even RG400 has it's limits I suppose.

Well that's it in a "nut shell".

Bruce Crain

____________________________________________________________
Jennifer Aniston: Should Rachel Have Ended Up With Joey?
firsttoknow.com

Checklists

Jay Scheevel

Hi Guys,

I am soliciting checklists that I can edit for my own use. If you have created those over the years and like your version, please post or send me offline. Many thanks.

Cheers,

Jay Scheevel, N8WQ Tri-Q, built, not flown yet.

Re: N46JP

Bruce Crain

Re: N46JP

Jim Patillo

Hey Bruce,

Nice to hear from you. Starting to get a lillle warm and humid in Okieville? Probably not much fun flying a Q in those conditions.

It’s 98 here (no humidity) in Auburn,Ca today, so I’ll head back to the Bay Area early tomorrow.

Saw \$5.00 a gal. Gas here today. California is beautiful but getting harder and harder for most people to stay here. People are baling right and left. The state government has gone completely off the rails with no end in site. The average price for an older 1600 - 1800 sq.ft. house with no land is approaching \$1.5M In the greater Bay Area. Disgusting! Our kids can’t live there anymore, just to expensive.

Oh well, fly on!
Jim
N46JP

Re: Honey Lamb and I

Bruce Crain

Re: Honey Lamb and I [2 Attachments]

Kevin Boddicker

Very good!
I did fly this morning, but it was windy, overcast, rough, and challenging.
Just what I like. Strange day. Cleared off then t storm, then clear, and just had a t storm move through now.
Tomorrow is supposed to be clear, but 20 to 30 with higher gusts.
Don’t like the weather?  Just stick around it will change!!!

Kevin Boddicker
TriQ 200 N7868B    453hrs
Luana, IA.

On Jun 2, 2018, at 4:59 PM, 'jcrain2@...' jcrain2@... [Q-LIST] <Q-LIST@...> wrote:

Honey Lamb and I bombed the National Bi-Wing Fly In! They were going to charge me \$5 until one of the men said “Well technically the Quickie is a Bi-Winger”. So we used the saved money to go by corn dogs and a funnel cake!
Bruce N Honey Lamb

From: Bruce Crain <bruce.crain@...>
To: Bruce Crain <jcrain2@...>
Date: Sat, 02 Jun 2018 16:51:09 -0500

__________________________________________________________
We Say Goodbye To Lara Spencer
risingstarnewspaper.com
http://thirdpartyoffers.juno.com/TGL3131/5b131395f3fb313953e15st04vuc

Re: Honey Lamb and I [2 Attachments]

Earnest Martin <MartinErni@...>

\$5 must buy a lot more in Oklahoma.

Earnest Martin
40 Glen Cove Drive
Arden NC 28704-3219
828-230-5378

On Jun 2, 2018, at 5:59 PM, 'jcrain2@...' jcrain2@... [Q-LIST] <Q-LIST@...> wrote:

Honey Lamb and I bombed the National Bi-Wing Fly In! They were going to charge me \$5 until one of the men said “Well technically the Quickie is a Bi-Winger”. So we used the saved money to go by corn dogs and a funnel cake!
Bruce N Honey Lamb

From: Bruce Crain <bruce.crain@...>
To: Bruce Crain <jcrain2@...>
Date: Sat, 02 Jun 2018 16:51:09 -0500

__________________________________________________________
We Say Goodbye To Lara Spencer
risingstarnewspaper.com
http://thirdpartyoffers.juno.com/TGL3131/5b131395f3fb313953e15st04vuc

Re: Honey Lamb and I [2 Attachments]

Mike Dwyer

The nerve of them trying to charge you \$5!
Good Job,
Mike, Bi-plane Q200

On Sat, Jun 2, 2018 at 5:59 PM, 'jcrain2@...' jcrain2@... [Q-LIST] wrote:

Honey Lamb and I bombed the National Bi-Wing Fly In! They were going to charge me \$5 until one of the men said “Well technically the Quickie is a Bi-Winger”. So we used the saved money to go by corn dogs and a funnel cake!
Bruce N Honey Lamb

From: Bruce Crain <bruce.crain@...>
To: Bruce Crain <jcrain2@...>
Date: Sat, 02 Jun 2018 16:51:09 -0500

__________________________________________________________
We Say Goodbye To Lara Spencer
risingstarnewspaper.com
http://thirdpartyoffers.juno.com/TGL3131/5b131395f3fb313953e15st04vuc

Honey Lamb and I

Bruce Crain

Re: Electric Q1

gbrighton@...

Thanks Henry,

Wondering how u reverse Thrust .. do u stop the Motor and then Reverse Motor .. or do u have a Reverse Prop mechanism ?

Would be a great reduced Landing Roll out feature ..,

Can u keep us posted with your progress PLZ ..,?

Cheers,

Graham.

Re: N46JP

Bruce Crain

Re: Electric Q1

Henry Hallam

G'day Graham,

Turning the prop backwards doesn't seem to be very effective at producing much reverse thrust, at least at low speeds (I've only tested up to about 20 mph).  I'm sure it's more drag than a stopped or idling prop but it doesn't augment the  plans soapbox-derby brakes as much as I'd like.  On the other hand, it's highly effective at making a lot of noise.  I'll see if it's any better at higher speeds.

Cheers, Henry

On Thu, May 31, 2018, 05:04 gbrighton@... [Q-LIST] <Q-LIST@...> wrote:

Bewdy Henry ,

Im sitting on a Tri Q ... waiting for electric population ... How are Reverse Thrusting ?

Cheers, Graham

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