DerJet F-35A
03-23-2016, 04:54 PM
#102
Yup landed too slow in a gusting headwind that dropped off at exactly the worst time. Rebuilding...but departing for Canada in a week as the IRS only allows me 182 days per year in the USA. My testing will resume in the fall again with a new left gear former and some other mods as well as a new set of nose gear rails. I believe Dave will have better results with his over the summer months and I can use his data as he's got mine from the 4 winter flights. I never got into the flaperons and stabs being deployed for landing test phase and that may have dealt me the bad hand on this one. It would land fast but very sweetly without bad habits...too slow and well we all know what happens when we do that. The "fast" landing would slow to a stop with regular braking in about 300 feet. There is a bright future for this aircraft, but my having only one day a week on the asphalt runway to test fly a newly designed bird was not the best judgement on my part... I should have shipped one to Canada too...just might after I get my taxes done!
Aloha,
Len
Aloha,
Len
07-13-2016, 02:14 AM
#103
F-35B Joel Vlashof
Hi guys, i am working to on the F35 model. I like the B version a bit more than the A version so i try to build The B version with the scale F135 propulsion system. Ror now i am working on the model but i found i hard to build the scale retract system, the dragbrace is difficult. here are some pictures. My B model is scale 1:8.5.
https://www.youtube.com/watch?v=EC2PJ8mYorw
Does anyone has any ideas. i think 3d printed parts are to weak.
Kind regards,
Joel
F35model.nl
https://www.youtube.com/watch?v=EC2PJ8mYorw
Does anyone has any ideas. i think 3d printed parts are to weak.
Kind regards,
Joel
F35model.nl
Last edited by joel.vlashof; 07-13-2016 at 02:24 AM.
07-13-2016, 09:47 AM
#105
03-09-2017, 10:43 PM
#109
Hi Guys,
Its been almost a year (7 months of it I spent in Canada) and with Obama here for December and some seriously unusual and poor weather this winter not to mention MCBH operations, I had not the chance to get flight #5 in until Feb 26th. It was a great flight, with BOTH main gear retracting! However; now the nose gear would not do so and it turns out that was an oversight on my part as it had a bent piston rod cross pin inside the trunnion from that bad landing on flight #4, and that added to the air flow force was enough to prevent the nose gear from retracting. However; after 3 laps trying to get them all up, I put the gear down and closed the forward main doors. The plane does get sweet to fly once those doors are closed, the same as the JL F-35 in Canada. Having slowed too much on the 4th flight for landing I was obviously running gun shy and landed waaay too fast and started the lateral oscillation that resulted in broken nose gear rails AGAIN. This time I have added 1/32" ply as upper and lower doublers and hopefully that will absorb more abuse without breaking...it may destroy the formers instead though. The plane is almost back together now and may fly again this Sunday or next weekend. Then I have to go back to Canada as the IRS will start charging me tax after the 182nd day.
I added a 3/4" nose retract riser as per Dave Wilshire's advice, and that nearly completely eliminated the looong takeoff runs. It now ROG's after about 320 feet. To be fair though I have a K-120G in there and that is a heavy engine for this plane. It would be fine on a JetCat P-100 or even the 90 that Dave uses. Not surprisingly, Dave also came up with another fix for the main gear not retracting which proved correct. He added about 10" of extra air line to the main gear lift cylinders and that allows the locking bar cylinders to do their work before the huge lift cylinders add so much force as to prevent the locks from opening.
The ailerons are now flaperons and they are lowered about 7mm for both takeoff and landing. Dave suggested I add about 10mm of up elevator to compensate for the flaperons, but I found that to be vastly too much and will go to 5mm for the next flight. I feel the added elevator was a contributor to the positive AOA gained when the locking bar cylinder and the other locking bar mount let go. Again this was from my landing vastly too fast. Eventually I will "get it" properly. The energy I was carrying and the added AOA from the mains collapsing due to the forces in play caused the positive AOA allowing the F-35A to rise to about 3 feet, stall, and drop onto the nose strut breaking the nose rails again.
I must say the weak nature of the former woods were a contributor as well. The main gear former I replaced in the fall was fine but the other side broke again. This is not a plane that lands all that easily or maybe I'm just intimidated by it. Dave said to fly it onto the ground and he is totally correct, but I was just carrying too much energy. I broke one locking bar cylinder piston rod end right off of the link. The other pulled out of the former again just aside the Hysol 9462 joint I had repaired it with last fall. Anyway Jack at Der Jet wanted me to post my experiences with the plane. My sense is that the wood needs an upgrade to real 5 and 7 ply aircraft grade plywood. That being said, if one is able to land this plane gently as its supposed to be done it would be fine. My first 3 flights were no issue on landing at all. I will get used to it sooner or later. The plane is truly gorgeous even after I have mucked up the underside. One great thing is the main doors never touch! The nose doors suffered a little last weekend but still held. So other than the nose former/rail issue nothing was damaged except a little wing tip on the lateral oscillation of course. All that was easily repaired though.
The original fin/rudder system caused some flutter on the first flight for both Dave and I and the Der Jet Factory consulted with and took Dave's advice and next to instantly re-engineered a new setup for the fin/rudder system that is much more solid and won't flutter. The new fins appeared at my mailing address within a couple of weeks. Der Jet always wants to hide all the control mechanisms for scale fidelity and while that is admirable, the controls need to be adequate for their task before being hidden. The factory acknowledged this and corrected the issue immediately to their credit. I have to say I have never dealt with any jet manufacturer on any continent that is more receptive to their customers and so quick to help in any way possible. For example the spare locking bar cylinder I need now was ordered last weekend and is now at the post office here awaiting pickup tomorrow!!! I cannot say enough good things about Der Jet's support, and believe me I was not the easiest customer for them to handle!!! Also in this light some things were determined that needed changes during my construction and new photos and instructions would appear in my email. Sometimes that was disconcerting, but they were always correct. From what I understand I was the first to fly this plane outside of the factory pilots, and as such I had less than perfect instructions, as no one knew what my setup was going to produce etc. I had a heavier engine but more thrust and several other new to the plane items like the gear sequencer and flight computer etc. All of this put me in uncharted waters to say the least...I must say that between Dave Wilshire and Jack Su I was well taken care of and at times I needed some serious care!!! The end result is a great plane that gets head turning all over the Marine Corps Base on which we fly.
Any questions...I am here to answer whatever I am able...
Aloha,
Len
Its been almost a year (7 months of it I spent in Canada) and with Obama here for December and some seriously unusual and poor weather this winter not to mention MCBH operations, I had not the chance to get flight #5 in until Feb 26th. It was a great flight, with BOTH main gear retracting! However; now the nose gear would not do so and it turns out that was an oversight on my part as it had a bent piston rod cross pin inside the trunnion from that bad landing on flight #4, and that added to the air flow force was enough to prevent the nose gear from retracting. However; after 3 laps trying to get them all up, I put the gear down and closed the forward main doors. The plane does get sweet to fly once those doors are closed, the same as the JL F-35 in Canada. Having slowed too much on the 4th flight for landing I was obviously running gun shy and landed waaay too fast and started the lateral oscillation that resulted in broken nose gear rails AGAIN. This time I have added 1/32" ply as upper and lower doublers and hopefully that will absorb more abuse without breaking...it may destroy the formers instead though. The plane is almost back together now and may fly again this Sunday or next weekend. Then I have to go back to Canada as the IRS will start charging me tax after the 182nd day.
I added a 3/4" nose retract riser as per Dave Wilshire's advice, and that nearly completely eliminated the looong takeoff runs. It now ROG's after about 320 feet. To be fair though I have a K-120G in there and that is a heavy engine for this plane. It would be fine on a JetCat P-100 or even the 90 that Dave uses. Not surprisingly, Dave also came up with another fix for the main gear not retracting which proved correct. He added about 10" of extra air line to the main gear lift cylinders and that allows the locking bar cylinders to do their work before the huge lift cylinders add so much force as to prevent the locks from opening.
The ailerons are now flaperons and they are lowered about 7mm for both takeoff and landing. Dave suggested I add about 10mm of up elevator to compensate for the flaperons, but I found that to be vastly too much and will go to 5mm for the next flight. I feel the added elevator was a contributor to the positive AOA gained when the locking bar cylinder and the other locking bar mount let go. Again this was from my landing vastly too fast. Eventually I will "get it" properly. The energy I was carrying and the added AOA from the mains collapsing due to the forces in play caused the positive AOA allowing the F-35A to rise to about 3 feet, stall, and drop onto the nose strut breaking the nose rails again.
I must say the weak nature of the former woods were a contributor as well. The main gear former I replaced in the fall was fine but the other side broke again. This is not a plane that lands all that easily or maybe I'm just intimidated by it. Dave said to fly it onto the ground and he is totally correct, but I was just carrying too much energy. I broke one locking bar cylinder piston rod end right off of the link. The other pulled out of the former again just aside the Hysol 9462 joint I had repaired it with last fall. Anyway Jack at Der Jet wanted me to post my experiences with the plane. My sense is that the wood needs an upgrade to real 5 and 7 ply aircraft grade plywood. That being said, if one is able to land this plane gently as its supposed to be done it would be fine. My first 3 flights were no issue on landing at all. I will get used to it sooner or later. The plane is truly gorgeous even after I have mucked up the underside. One great thing is the main doors never touch! The nose doors suffered a little last weekend but still held. So other than the nose former/rail issue nothing was damaged except a little wing tip on the lateral oscillation of course. All that was easily repaired though.
The original fin/rudder system caused some flutter on the first flight for both Dave and I and the Der Jet Factory consulted with and took Dave's advice and next to instantly re-engineered a new setup for the fin/rudder system that is much more solid and won't flutter. The new fins appeared at my mailing address within a couple of weeks. Der Jet always wants to hide all the control mechanisms for scale fidelity and while that is admirable, the controls need to be adequate for their task before being hidden. The factory acknowledged this and corrected the issue immediately to their credit. I have to say I have never dealt with any jet manufacturer on any continent that is more receptive to their customers and so quick to help in any way possible. For example the spare locking bar cylinder I need now was ordered last weekend and is now at the post office here awaiting pickup tomorrow!!! I cannot say enough good things about Der Jet's support, and believe me I was not the easiest customer for them to handle!!! Also in this light some things were determined that needed changes during my construction and new photos and instructions would appear in my email. Sometimes that was disconcerting, but they were always correct. From what I understand I was the first to fly this plane outside of the factory pilots, and as such I had less than perfect instructions, as no one knew what my setup was going to produce etc. I had a heavier engine but more thrust and several other new to the plane items like the gear sequencer and flight computer etc. All of this put me in uncharted waters to say the least...I must say that between Dave Wilshire and Jack Su I was well taken care of and at times I needed some serious care!!! The end result is a great plane that gets head turning all over the Marine Corps Base on which we fly.
Any questions...I am here to answer whatever I am able...
Aloha,
Len
03-10-2017, 04:03 AM
#110
Thread Starter
Len
Well done for sticking with it. I hope to get out with mine again soon, the winter is almost over and we start to get airfield access again in the next couple of weeks.
Some of my early landings were not the smoothest and my wood work has held up fine, the nose rails are long and unsupported, the packing can be used to spread the load here.
Its undeniable that people love the 'mean' look, its just one of those aircraft that is more complicated than it looks...and was designed to be flown by a computer!
I hope to have a full summer with mine
Dave
Well done for sticking with it. I hope to get out with mine again soon, the winter is almost over and we start to get airfield access again in the next couple of weeks.
Some of my early landings were not the smoothest and my wood work has held up fine, the nose rails are long and unsupported, the packing can be used to spread the load here.
Its undeniable that people love the 'mean' look, its just one of those aircraft that is more complicated than it looks...and was designed to be flown by a computer!
I hope to have a full summer with mine
Dave
03-29-2017, 05:49 AM
#113
Thread Starter
If yours is the later kit with central hinged rudder you should have no issues. I have not flown the new fins yet, but the exterior linkage solved the flutter problem on the live hinge version.
We have a meeting in 2 weeks where I hope to get some more hours on the F-35.
Give me an email address and I'll email draft instructions [email protected]
Any photos you need too.
Dave
We have a meeting in 2 weeks where I hope to get some more hours on the F-35.
Give me an email address and I'll email draft instructions [email protected]
Any photos you need too.
Dave
03-29-2017, 08:46 AM
#114
Len
04-03-2017, 09:54 AM
#115
Hello Dave. Thanks for doing all the beta testing 
. My Email is [email protected]
Will be starting the build in a week or 2.
. My Email is [email protected] Will be starting the build in a week or 2.
If yours is the later kit with central hinged rudder you should have no issues. I have not flown the new fins yet, but the exterior linkage solved the flutter problem on the live hinge version.
We have a meeting in 2 weeks where I hope to get some more hours on the F-35.
Give me an email address and I'll email draft instructions [email protected]
Any photos you need too.
Dave
We have a meeting in 2 weeks where I hope to get some more hours on the F-35.
Give me an email address and I'll email draft instructions [email protected]
Any photos you need too.
Dave
04-15-2017, 01:14 AM
#116
Thread Starter
Essential RC got another flight on video at a blustery CJ yesterday. Will finish up the manual now
https://www.youtube.com/watch?v=sksjcr32hqo
https://www.youtube.com/watch?v=sksjcr32hqo
04-15-2017, 09:24 AM
#120
Thread Starter
Yes, when the nose doors are open the huge 'turning vane' has an affect on yaw, then when the front main doors open, it also dumps lift. Its why I fly a circuit gear down, cycle the gear away and visually check. If you get a door stuck or leg hang it gettings messy!
04-15-2017, 12:45 PM
#122
Thread Starter
Len. Its very stable in pitch, but the gyro certainly helps on landing, it keeps it stable in the HA angle it needs to land at. Yaw is good to stabilize things with the gear doors open. So yes an aileron only gyro would sort out the roll damping, but I think you would gain from a 3 axis unit.
