Colin_Mc

Oh and any scots (Alasdair?) that want a cf small dia spar let me know as there is enough left to make 2 more.

fireblade5437

How I did my woodwork on F120. Jet 1A

Alan

JetCatJimmy

That is a really cool idea. I think I'll add that to my build. Thanks for the explanation.

joeflyer

My Feedback: (48)

Tom,

The Falcon will tend to leap off the runway if it has a negative angle of attack. It's best to have a couple degrees of up attitude, however you should be OK at zero.

How are you measuring the angle? With the plane sitting on a level surface the center of the wing airfoil at the LE should be slightly higher than the center of the wing TE.

Joe

Jetpilot24

My Feedback: (21)

Tom

My falcon sits with 0 degres angle of attact. I use 1/2 flaps on take off About 25 to 30 degrees, she does a nice clean take off. I have tried no flaps and the takeoff roll is longer and it POPS offt the runway. Using the flaps solved this tendancy.

Joe Lewis
KingTech
K-80 owner

Colin_Mc

Thanks for that, anyone done the same with a rail mounted nosegear retract? Photos would be helpful as i'll soon be at the stage of putting the formers back in

Tom in Cincy

My Feedback: (16)

Thanks Joe & Joe. I was using my new angle measuring device. I set the table top level as zero and then measured along the bottom of the fiber fuse just behind the front wheel well and then measured the angle of the flat bottom wing. All showed close to zero deg. I tried measuring the leading edge/trailing edge centerline heights from the table top with a ruler and they measure very close to the same. So it looks like I'm at zero - zero.
I have read that mixing in down elevator with dropping of the flaps is the correct way to go. My full flaps are set to 45deg and I was going to mix a 1/8" down elevator. Does that sound right?
I will try the maiden at 25 deg for takeoff. I have flown the "bobcat 52 pusher" and noticed this plane wanted to pop-off instead of a smooth rotation and fixing the the landing stance to a positive degree took care of the problem. Raising/lowering the falcons retracts are a bit more challenging.

joeflyer

My Feedback: (48)

Yup, that's what I use.

My wing LE is about 1/2 inch higher than my TE close to the fuse, and my take offs without flaps are very smooth. See how it goes with flaps. You could also try a bigger nose wheel if practical.

Good luck,
Joe

Jetpilot24

My Feedback: (21)

Tom

I didn't use any down elevator for mine. It did not seem to need it. I balanced it at 13-1/8 of an inch from the leading edge of the wng. That worked perfect. Sounds like you have the correct amount of flaps.

Joe Lewis
KingTech
K-80 owner

ticketec

My Feedback: (2)

Mine is almost ready to go as well.

Just some minor jobs left to do on her and then setting the control throws and expo's.

Thanks

Dave

BaldEagel

Well chaps I use 90deg or flap to act as an airbrake and 20mm of up aileron at the same time to add wash out to the wing for very slow short landings, in the UK our landing strips are not as long as yours in the US so we need to be accurate and slow to land on the patch, which incidently is a mown strip in a sheep field, have you ever tried to get sheep poo off your airframe after it goes hard, I think it could be used as a substitute for Hysol. LOL.

Mike

david101

My first attempt to get pic's of simple wood engine mounts for my P60. No promises as I am not a computer geek.[img][/img][img][/img]
Aluminum under engine platform is 1/2" x 1/2 angle to reinforce mount x 2.

david101

Second pic.s


[img][/img]

david101

I notice that in post 3480 as on my Falcon that there is a gap at the canopy front. Has any-one had theirs blow off in flight??????? Should it be necessary to close the gap so air pressure will not tear it off or??????????

Also for those doing rail mounted retracts, I was able to use the existing rails etc. using Springair's and was able to shorten the gear(5' belly of fuse to ground) by moving retracts back and the nose gear wheel well foreward as far as possible. Used a 2 1/4 ' wheels and bent a new nose strut of 3/16 mw.

Now installing ecu, brake control, fuel tank, rec , batt's etc.

Dave

BaldEagel

David

Please don't take these comments as critisism, Just trying to help, but have you reinforced inside the fus to take the angle's for the engine mount?

The UC mounts on mine where not glued in sufficiently to be reused without a lot of work to reinforce the ribs they where attached to, in fact when I drilled into them they fell out, so did all the fus formers when I flexed them a bit.

Mike

ticketec

My Feedback: (2)

Hey Baldie

Yes i did mate... folded to peer group pressure and basic engineering facts. I drilled through the engine mounting plate on the left and right hand side from the rear, and then hysol'd 6mm carbon spars into the holes. with the spars running from the back of the engine mount to the first former inside the fuse.

I still believe that the locating pins on the trailing edge of the wing would be more than sufficient support as the wing root in that area is nearly 1/4" ply, but i didn't do it in the end because i would be drilling through my 6mm carbon stiffeners i had just installed[X(]

Anyone been able to get onto Sandor from Digitech? I have Pm'd him and sent a message though his website to buy a set of his "raw" trailing link legs, but have not heard from him. it's unusual for him not to respond in my experience.

Thanks

dave

BaldEagel

Good to see someone else using that idea, I used 10mm rods as I was using a P80 in my version and had totally changed the inside layout to give me clear access to all the gubins we have to use.

The P80 is also the reason for having the flaps go down to 90deg's the tickover thrust is quite high and the Falcon is quite small for it, but it is overpowered.

Mike

tim777jet

Ref possitive nose up angle on the ground. My fisrt attempts with my engine dialed down to around 13 lbs of thrust just led to the plane running along the ground at high speed. I have possitive nose up when she sits on the ground and rotation is excellent without any fus and no flaps, off really rough grass and engine cranked up to 14 lbs.
If you have too much nose up, no probs with take off, but after landing the plane can suddenley point skywards and nose dive in the ground. I ripped off my nose leg due to this, twice, hence the reason for my home made nose leg phenmatic extension system, which reduces length of nose leg when full flap selected, keeps the plane planted during the roll out. If you have tarmac runway, might not have too many issues with low possitive nose angle for take off, but i would definately have some, cheers tim

BaldEagel

Tim

Did you ever try freflex on your ailerons because I think this would work to stop the dreaded bounce on landing as it spoils lift over the wing and you have to hold off with elevator, so on landing the amount of lift generated by the wing is insufficient to lift off again, I'v been using this on all of my airframes for the past 10 years without finding an aircraft that does not beniffit from it, I have mine as an adjustable amount on a side slider with the switch being the throttle so if I have to abort a landing when I open the throttle the ailerons go back to center, try it it rearly works.

Mike

david101

Thanks for concern. Yes I added plywood with epoxy inside the fuse to strengthen internal structure under engine mount. Lg. appeared well glued but added fillets of epoxy to all related areas. This may have been a "good "build as I had trouble removing several formers.

Concern now is with front of canopy gap to fuse. May add thin plastic or metal fairing to fuse to shield canopy gap from air entry. Thoughts?????

Also considering removing about 1" or more from each wing tip to aid loading plane assembled into my mini van. Possibly add tip plates too.

Dave

w4sm

I'm a big fan of reflexed ailerons as well. Decreases lift to aid landing, prevents tip stalls, prevents landing bounces, etc. My Falcon 120 sits with virtually 0 degs of incidence. On a grass field, I use half flaps for takeoff, run the turbine up to full with the brakes locked and then release the brakes. Because there is a LOT of weight on the nose gear with the proper CG (mains are designed too far back), it takes a fair amount of speed to get enough elevator authority to rotate the plane. Don't be afraid to yank back on the stick to get the nose off, then let off some. Given how fast you need to be going for the elevator to have this much control on the ground, you won't stall unless you just keep holding full up!

BaldEagel

Stacey

Don't have any problems rotating, my field is so bumpy it takes off when it reaches a bump on the front leg and this gives it the neccesary positive incidence, I think the problem most are having is because of the up thrust from the tubine everyone seems to need, I put mine in level and put a mixer on the throttle too elevator to compensate, havn't burnt the tail yet!!!! but then I don't taxi down wind or have to wait to take off, everyone stop when I fly it for some reason, I hope its because they want to wach rather than being a comment on my ability. LOL.

Mike

P.S. see you have an Elan in your Avatar, I just wrote mine off, curvature of the earth caught me out.

TCHIEF

My Feedback: (15)

I guess the eagle and i are the only ones who dont feel the need to put a thrust angle on the engine I have flown mine like this since day one. Mine sits with the TLRA rule for incedence and last weekend for just to see what happens when i got ready to rotate instead of just pulling pack on the elevator i gave it a quick pull and released it the nose came up very smooth and it ran on the mains for about 10 feet and lifted off with no other inputs I also have not had the kangaroo syndrom of bouncing down the runway.The only thing I have noticed is i didnt set my timer one flight so i cut it short landed with falf full tank and it settled better with more weight on board

gchdavid

Hello guys,

I haven't posted in a few weeks due to wedding planning and business stuff but I have gotten some stuff done here and there.

Here are two pics of my brakes that I machined via CNC. I made a "drum" to bolt/pin to the wheels I purchased which didn't have provisions for brakes (you can see my posts a few pages back) and then I machined a brake in which to put a 1" diameter 1/8" round or square O-ring for breaking. So far everything fits great in my homemade struts. I will post pics of the entire thing assembled together soon.

Still have to drill and tap for the small air nipple to actuate the brakes. Other than that landing gear is finished!

Best regards,

Chris

BaldEagel

Chris

Are you going to use pistons to move the O ring or are you relying on the seal between the O ring and the grove to keep the air in when you actuate the brake?

Mike