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captarmour

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Feb 9, 2013
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Roseau, Dominica.
Hello... Just one picture to update the status of my project, on going building phase.
Regards.
GTex09
View attachment 24427
I want to applaud you for your courage and resourcefulness, in going ahead with this project and sharing so openly with us. This is really inspiring and an example to those who keep raking in investment money and show little for it. I hope all of us at homebuiltairplanes support you and encourage you. keep up the good work.
 

gtex09

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Apr 13, 2010
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France (Lille)
Thank you for your encouraging comments, Captarmour.
Of course as soon as I can I will post more pictures of my scale 1:1 (GTx9-11-C).
Rgds
gtex09
 

Jay Kempf

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Warren, VT USA

berridos

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Oct 10, 2009
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madrid
Wooow havent noticed this thread. Impressive project. Are you aware that you are close to producing the first stealth homebuilt? Just avoid some curvatures
 

Jay Kempf

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Hereby some more pictures during prototyping...
Actually the tricycle gear is retractable, but I will not activate from the very beginning of trials, to not add to much critical things.
:)
View attachment 25053View attachment 25054View attachment 25055View attachment 25056
Really nice stuff. I am lost in CAD world on a clients project and it is nice to see actual pictures of actual parts. I like the way you have just used the struts and made simple and robust attachments. I also like the combination of simple 2 and 3d milling and sheet metal. Very manufacturable. Nice stuff.
 

captarmour

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Feb 9, 2013
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368
Location
Roseau, Dominica.
Hi,
Weather is nice today...it's time to take some sun. Some news of the scale1:1 GTx9-11-C. Next step is related to the short wings assembly.
Keep posted.
Rgds
View attachment 25041View attachment 25042View attachment 25043
wow! simply fantastic! keep up the good work!

is the nose wheel free castoring or is it steerable?

from the side view the axle looks ahead of the steering axis. like on a motorcycle if a straight line is drawn from the 'neck' or steering pivot or axis, to the ground, the axle should fall behind, or 'trail', that line for stability, (like a shopping cart steering).
 
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Workhorse

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Mar 6, 2010
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400
Location
Southern Spain
Hereby some more pictures during prototyping...
Actually the tricycle gear is retractable, but I will not activate from the very beginning of trials, to not add to much critical things.
:)
It looks impeccable. Those are motorcycle forks, are you sure they could stand the loads of a landing gear?. Weight distribution in bike I think is not 50/50.
 

gtex09

Active Member
Joined
Apr 13, 2010
Messages
38
Location
France (Lille)
Certanily helps to answer the question of how to use motorcycle front forks.

Great build gtex! ;)

Hi 'cheapracer'
Well, actually, what I did is... look around me, with my friends (motos) what kind of stuff I could use to make it cheap !
What is a main gear, hydraulic, for a plane ? If you check for the load, you can adapt the spring of a bike fork, like the Ducati Monstro (Showa), which is having a mechanically well guiding piston. The diameter and materials are very similar for the ones we know on aircraft....So just a couple of calculations, drawings, on how to adapt it, and that's it. I bought wheel from 4x4quads, and hydraulic disk brakes, then ones from small bikes, and then made the necessary adapting parts. I use ball bearings ('O' mounted) on a strong steel shaft, which is fixed on the extremity of the fork piston. To absorb the cinetic energy on landing I need some 150mm, maximum, which I will take splitted 30mm on the tire and 120mm on the cylinder. I will adapt the internal spring to the revelant force for this....It will work...:)

TPAL drawing extract.jpgP1020201.jpgP1020206.jpgP1020213.jpgP1020518.jpgP1020519.jpgP1020524.jpgP1020527.jpgTPAL calcul resistance axe.jpg
 

gtex09

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Apr 13, 2010
Messages
38
Location
France (Lille)
Hi Captarmour,
Yes, steerable, it will be easier to steer the machine.
For stability reasons I applied the angle like on bicycle forks (21°) and the positionning of the steering column axis behind the wheel axis, intersecting the wheel radius at around 0.25xR, as I already tested in my GTx9-09 model. ;)
TAV Stability.jpg
 

gtex09

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Joined
Apr 13, 2010
Messages
38
Location
France (Lille)
Where is the part 3 where it flies ?
We'll see... If weather, finances, time are OK, I hope being able to run part 3 by next spring or summer... I steel need to buy the gear between engine and propeller, need also to mount the engine (the BMW motorcycle is already bought, but I've to adapt the engine to my wing, with frame, and all equipments...) I also need to buy the propeller....So 'part 2' is not finished yet, but I forecast to be ready for some engine ground testing by next autumn.
Keep posted !
gtex
;)
 

captarmour

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Joined
Feb 9, 2013
Messages
368
Location
Roseau, Dominica.
Hi Captarmour,
Yes, steerable, it will be easier to steer the machine.
For stability reasons I applied the angle like on bicycle forks (21°) and the positionning of the steering column axis behind the wheel axis, intersecting the wheel radius at around 0.25xR, as I already tested in my GTx9-09 model. ;)
View attachment 25083
I can see you have done your homework.
In this diagram the 'trail' looks like zero, and does not show the decrease in steering angle of the leg as the front lowers under compression like in heavy braking for example.
Most motorcycles have about 4 inches of trail with about a 25 to 30 degree 'neck'. 21 degrees is steeper than on a motorcycle, probably the much larger diameter wheel of a bicycle improves stability as compared to a motorcycle. With such a small nose wheel it may be better to err on the conservative side.
 

cheapracer

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Sep 8, 2013
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Australian
In this diagram the 'trail' looks like zero,
Most motorcycles have about 4 inches of trail with about a 25 to 30 degree 'neck'. 21 degrees is steeper than on a motorcycle,
Strange, I thought I answered this one - Cap is correct, there isn't enough trail by the looks of it but rake actually matters little unless of course the rake is the determining factor for the trail.

I am wondering/asking if anyone has any information on this picture?View attachment 25533
http://www.homebuiltairplanes.com/forums/aircraft-design-aerodynamics-new-technology/6806-slow-delta-wings-9.html
 
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