LUDS96

My Feedback: (23)

KC. I looked at your profile Nice Quiver of Planes. You can certainly share some jet experience. Thanks for sharing with us prop jockey's

gsoav8r

My Feedback: (6)

Some have already seen these: sbrackets, patzane, maybe a few others.

The runway is 40x400. The grass area is rough and you cant taxi on it. Running off the tarmac at more than a walk usually results in a bent nose gear. Anyway vid one shows what can happen if I land long and run out of runway. Vid two is a good example of not hitting the numbers and riding the landing out in ground effect.

Be sure to look under the views count and watch in high quality.

Cheers,
James

http://www.youtube.com/watch?v=rGZFYosR1tE

http://www.youtube.com/watch?v=1C5OH9Re3NQ

sbrackets

Hey Guys
I have started to pull out the broke plywood the supports the retracts in the F-16P, Or should I say, the wood about came out on it's own. Cermark F-16 makers didn't even use 1/4" plywood, they used two layers of 1/8" plywood sandwiched together and the two layers weren't even glued together. Pretty sad building.
I have one more retract assembly to remove before I start to replace the wood rails.

My question is what type wood should I use to rebuild my retract rails with? Spruce, Poplar, Maple?

Your feedback will be greatly appreciated

Thank you, Jim S.

miklos

My Feedback: (38)

Well, another frustrating day at the field. Took the F-16 out Saturday after repairing all 3 gear mounting blocks. Set up for take off and gunned the throttle and she began her takeoff roll. Got about 3/4 of the way down the grass runway and the front gear collapsed like a " cracker". The other guys at the field who had a better vew of it than me since I was right behind the plane for the takeoff roll, said it looked the the front gear bounced up, then when it came down, it hit a rut in the field and collapsed. Friday I had it out also and bounced the landing and the gears remained intact! Had to abort Fridays flying session due to rain. Now I have to repair the front gear again and I just don't know if I have it in me to keep fighting this fight. The plane looks so sweet when airborne though, but this time I have to repair not just the front blocks, but the formers as well, and a little patch work on the fiberglass fuse also. Right now I have too many coals in the fire to keep puting so much time into this one. Oh well.... I'll have to make time!![:@] It's a shame such a fine looking kit is compromised by such poor quality wood!! Come on Cermark step up to the plate!

gsoav8r

My Feedback: (6)

Hi Jim,
When my gear blocks got trashed I replaced the cheap 6mm (1/4 in) 5 layer plywood with 2 layers of high quality 1/8 inch 5 layer ply. The two layers of 1/8 inch ply were epoxied together to make 1/4 in - 10 layer ply gear blocks. I believe the wood is poplar.

Only reason I used this method is because its what I had in my shop at the time and didnt want to chase material.

A couple reasons I say the stock gear material was cheap is because the wood was very soft and after cutting thru a couple of sections that were not splintered I found voids in the ply. Definitely not what would be considered aircraft grade.
I couldnt begin to guess why the material in the plane I have and the plane you have is/was different. wow.

For the rebuild I also installed blind nuts and socket head screws to fasten down the gear. My plane just came with screws that were easily stripped out of the cheap ply.

Over a year later my gear are still holding strong.

Cheers,
James

LUDS96

My Feedback: (23)

Miklos! I feel the same way about this plane sometime's But I don't get the kick from my other planes that I get from this one. It's one or two Graet flights than and Hour or two of repairs to the gear. Try putting a single piece of light ply in the nose like in my earlier post. It is surely is worth the time. I lost a main gear on the field that day you saw mine flying. Hit a big chunk of wood on the field. Who knows. Give us something to do!

LUDS96

My Feedback: (23)

Great Video's Thanks for posting. Did I hear the ventral fins hit the ground when you landed. I don't have mine on.

Robert Groves

Hi Jim

Congrats on the maiden, great video and great looking plane, I like the strut btw!

It looks like my maiden all over again, except you managed to put it down way better than I did.

What expo are you using? I found my 15% works very well.

A bit of advice I want to offer if I may, when you are flying this bird, it becomes very obvious that the nose is easier to raise when the fuel is lower, which is the reason I was "balooning" the plane on landing, which seems to be what you did as well.
On landing keep elevator feed and play with throttle more, if you find yourself pulling back "hard" on the elevator when the plane drops, chances are your plane is going to gain height and loose momentum.

My experience in jets is limited to this plane, but from what I see momentum is the name of the game here, without it you can get bitten badly!

The only way I got this right was finding a suitable flight sim plane.

Cheers

Rob

TXKflier

Which flight sim and/or plane?

Thanks,
Lynn

Robert Groves

I learned to fly initiall on the Reflex software a year ago! (after 20 hrs I did my solo in 2 weekends.)
They have a few downloads on their product store, one of them being an F15.
Although I have never found the sims very accurate, by playing around with the dimensions of the F15, I was able to make it fly like a man hole cover!
By controlling throttle only, with constant elevator, it gives you the just of how to land the F16 from Cermark.
After2 hrs of this, my first landing was as smooth as silk!

Hope it helps.

http://www.reflex-sim.de/reflex-sim/shop/catalog/

sbrackets

Thanks Robert and everyone eles with the advice, It's well taken. The only damage I took from my crash landing was the landing gear support wood. The bottom fins were OK! I believe what saved them was thart i still had a good left main gear and the O.S 91 FX muffler hung down low enough that both keep the belly from coming in contact with the ground. The fiberglass has only small cracks around two of the wheel wells where the gear was forced back up inside the fuselage. I was were lucky this time. I was given a second chance
I know now that I cut my flight short. I should have stayed aloft longer to burn up more fuel, But reading the forums you hear where folks seem to run out of fuel in a short time and I was afraid of that. After I crash landed I saw where I still had 3/4 of fuel left in the tank after a good 5 min. flight. So yes the nose was still to heavy with fuel and I'm sure that added to my crash landing.

As for my Expo mix in the radio, I believe it's set at 25% on the elevator at full rate. The plane just felt a little heavy/ slow to my responces when I pulled back on the elevator stick. Too much expo I believe.

When I took off I had my ailerons set at half rate, then switched to full rate once in the air. OH well She'll fly again, Will post some photos of the belly damage for you all to see later today. I believe I'll even add more photos has I perform the repair job so others can see how to fix there F-16 in the future.

Regards, Jim

Robert Groves

Good to hear Jim!
I got some fixing to do too on the wheel arches, I still have 1 original I need to pull and and replace.
Cracked the fuse again on a hard landing !!!![:@]
Could kick myself!
Change those muffler bolts!!! just in case, and check the muffler isnt cracked.
You dont want the muffler coming off next flight!


R.

gsoav8r

My Feedback: (6)

Hi Luds,
Ive never had an issue with the fins except when they were damaged on my maiden.
I believe what you heard was the tail cone hitting the tarmac.

Regards,
James

miklos

My Feedback: (38)

Well, got down to it last night and finished patching up the front gear and block. She's ready for another try hopefully this weekend.
By the way, it would be really helpful since all 3 of my orginal blocks are trashed if someone had a PDF drawing of the original gear blocks so that next time mine broke, I could just trace a new set onto a piece of wood and cut them out instead of haveing to reengineer them every time.
Anybody??

sbrackets

Hey Mike
I too was working on my gear blocks last night, I ended buying a sheet of 1/4" Hobby Plywood instead of trying to find some Maple or Spruce hardwood.
I know what your talking about on the gear blocks. I search on the web before I starting the rebuild. I couldn't find drawings or anything. So again it's up to me to figure it out.

Instead of going back with the "U" shape retract mounting plate. I am just going to install (2) 3/4"W x 4"L x 1/4"H strips into the female slots between the fuselage bulkheads for each gear. Glue them in place with CA.
Then underneath the 4" strips, glue another 1/8" H x 3.5"L x 3/4" W Plywood strip snug between the two bulkheads. This will keep the "NEW"gear block from shifting foward or aft. between the two bulkheads. When all wood is set in place, glued into place , then mark your holes and drill them. Secure with whatever hardware you choose.

If they break again, all I have to do is use some De-Bond agent on the CA. and remove the broke wood and replace again.

I will be glad to post some photos if you like.

Regards, Jim S.

miklos

My Feedback: (38)

Thanks sbracket... That's pretty much the way I did it this last time on the nose gear bracket except I epoxied all wood in place. The CA idea sounds good though as it would be nice to be able to remove the broken wood without too much hassle.

DamBo

I have a question about the cg. Book says 8.5" with this setting I need 12oz of lead in its pants.
Does this sound right. I am not using anything special.SJ90LX and A123 battery pack in the rear.

sbrackets

The book is wrong! Correct CG is 7.5" .....With the fuel tank empty and the retracts in the down position measure from the leading edge of the wing at the root, mark back 7.5". That should do ya.

Mine flys good at that setting, and this setting is for the latest version 3.

Jim

phjoker

My Feedback: (4)

sdbrackets is correct.
Thats where mine is ballanced. 7.5" back.
I also had to add some lead to the tail but it wasn't much.

DamBo

Good deal.

Maybe I'll get a chance to fly it tonight.

Are the default throws correct?

Thanks

Hot Rod Todd

My Feedback: (1)

I would make sure you have plenty on the elevator. As you come in to land with some angle of attack the elevator seems to be blocked by the wings or something, making more throw needed to be effective. I don't know what mine is right off hand, but I have to land on high rate to make sure I don't plop it in due to lack of elevator.

gsoav8r

My Feedback: (6)

Dito what Hot Rod Todd wrote.

I think the default throws are OK to start. I think you will find you will want to adjust it later thou as you become more comfortable with your plane.

I have cranked up the throw on my elevators to 120% and dialed in more expo. 35% I think...Id have to check to be sure. This was mainly to suit my flying style of not needing to flip switches between high and low rates. I fly with high rate elevator the whole time.

I rarely use high rate aileron as I find low rate to be plenty. Agian a style preference.

Good luck.

sbrackets

I believe that the reason I crash landed my F-16 last week I didn't have enough throw on my elevators. Went back and checked the throws and was set at 3/4" U&D, should have been 1" U&D maybe even more. I have since gone back and made the correction to my radio.

Jim

KC36330

on the full flying stabs set it up with all the throw you can get without putting the linkage at a mechanical disadvantage.

miklos

My Feedback: (38)

Ok.... after the umpteenth torn front gear block this weekend, [:'(]I decided to bite the bullett and order a new fuselage from Cermark.[:@] Well, surprise, surprise..... they're out of stock for 3-6 months. [:-] So last night it was back to the building table. I'm runing out of places to put epoxy on this baby. I really wish I could just yank the cheap formers and fabricate a new set out of some good ply, but that would require a template. If they can't keep the parts in stock, it would be nice if Cermark could provide us with templates for the formers so we could fabricate new ones and really get these babys fiexed right. Oh well, wish me luck.