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Old Oct 18, 2010, 11:53 AM
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"Aircraftus Fragmentum"
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United States, MI, Detroit
Joined Mar 2007
4,369 Posts
Quote:
Originally Posted by Mike_Then View Post
Hi Neversommer, I did have some control issues which I will describe below. I don't have any other HL jet but my friend and club-mate had the Eurofigher and I know this jet is significantly faster than the Eurofighter.

Okay, here's my flight report from Sunday. Sorry I didn't get it updated yesterday; long day at the flying field, my turn to cook dinner, then had to watch the football game.

Flight #1, first attempt:
Checked the balance again, and range-checked OK. Used the recommended throws for both the elevator and ailerons (1/2" low rate, 3/4" high rates). Checked the amp draw and watts before the 1st flight; 71A at WOT fresh off the charger and 1600+ watts. Should be more than enough to move this plane with authority. Lined up on the runway and smoothly advanced to full power. Plane would not lift off the ground. I switched to high rates right before I had to abort and the plane still wouldn't take off. Aborted the takeoff and as the plane was rolling to a stop, the left-rear wheel fell off. Further investigation shows the little plastic cap got so hot from the wheel hub rubbing against it that it melted the plastic a bit, causing the wheel to fall off. Brought the plane back to the hangar and fixed the wheel.

Flight #1, second attempt:
Lined up on the runway and advanced to 100% throttle, this time using high rates the entire time. Same result as last time, the plane did not lift off and the left rear wheel fell off again. Brought the plane back to the pits and found the same results as last time, except this time the wheel and the nut were both damaged/melted a bit worse. Fixed the wheel and nut with a drill bit and CA. Also saw that the nose gear was loose, as the screws were backed out a little bit. As I tightened them up, you can feel the screws just turning so that means these holes are stripped too. I will have to strengthen them with some CA.

Flight #1, third attempt:
Took the plane to the road at our field. Lined it up and advanced to 100% throttle. This time the plane leapt off the ground and was airborne. It needed A LOT of right-trim and A LOT of up-trim. Flew for about 3.5 minutes and landed on the grass runway without issue. Batteries were warm (not hot) and read 11.1v each so that means I used 80% of the packs. Probably due to the full-throttle blasts for three takeoff attempts.

Problem: Worth noting is that no where in the manual does it state what the neutral point is for the elevators, so that's part of the takeoff problem which was a lot of down-trim. The small wheels didn't help things in the grass either.

Solution: I increased the amount of throw for the elevators and also evened them up (which allowed me to take out some of the right-trim). The only reference point I had to line them up was lines in the fuselage but they proved to be wrong. I'm pretty sure that the additional throw was needed because I did not have the TV enabled.

Flight #2:
With more elevator throw and a washer on the left-rear wheel to hopefully act as a bearing, I tried to take off from the grass again... the plane is useless to me if it can't be flown from our grass field. I used most of the runway but it finally took off. It's a bit sensitive at this point with all the elevator throw I added but it's manageable. Nothing a little expo can't cure. Took out a little right-trim so now I'm making zoom-and-boom passes and exploring the flight envelope. It grooves very nicely and looks fantastic on high-speed passes. Loops are big, and vertical performace is OK but it runs out of steam on the upline rather quickly. The plane is quite fast in level flight at 100% throttle. Flew for exactly four minutes and set up for landing. There was a nice breeze right down the center of the runway and I was pleasantly surprised at how slow it flew with not a hint of stalling. Set it down gently and taxiied back to the pits. Batteries were warm (not hot) and read 11.3v so I had a bit more flight time.

Flight #3:
This time the plane jumped off the ground quickly but I honestly think it was because I hit an ant hill on the runway (see below). Flew for 4.5 minutes and landed with warm batteries and 11.2v in the packs. I'm thinking at this point I can get 5 minutes from 4000 mAh packs if I'm careful with throttle management.

Flight #4:
The F/A-18 used most of the runway again and wouldn't come off the ground. Just as I was about to abort the takeoff (I had pulled the throttle back at this point), the plane jumped off the ground at the end of the runway and ripped the entire left gear assembly out of the fuselage. I'm now 10 ft. off the ground, low and slow. I punch the throttle and it climbed smoothly and got on-step quickly. A slow pass confirmed the entire left gear missing. Since the landing may not be pretty, I might as well enjoy it while I can. I explored more of the flight envelope, made a few photo passes, victory rolls after high-speed low passes, etc. Decided to belly-land the plane rather than risk a 2-gear landing. Plopped it on the runway as slow as I dared and thankfully it didn't rip off the missiles. It chewed up the foam around the intakes and the nose, but nothing major and nothing that can't be dressed up with a little sandpaper and some grey paint. The gear unit was found to be intact and worked perfectly, so that's good news. Further good news is that the plywood plate was also intact. As the picture will show once I get to my home computer, there was minimal amounts of glue holding the plywood mounting plate into the plane.

So here's my punch list to get the plane back in the air:
  1. Glue the left-rear gear back into the airplane.
  2. Rip out both other gear mounting plates and glue much more securely.
  3. Change to bigger wheels for grass-field takeoffs (there's plenty of room for larger wheels).
  4. Change the axles to something larger and with better ways to secure the wheels.
  5. Sand down and paint the chewed-up foam on the belly.
  6. Glue some lite ply to the floor of the battery compartment so straps can be utilized to further secure large packs (the included straps weren't long enough and were removed from the aircraft).

My suggestions for the V2 kit of the airplane for Hobby Lobby:
  1. Manual addition: Please mention how and when to mount the wingtip rails and missiles.
  2. Manual addition: Please mention how to center the elevators.
  3. Manual addition: For those using the thrust-vectoring, more details and/or clarification is needed as the TV just has a passing mention in the manual.
  4. Slightly larger wheels (remember a large percentage of us do not have access to paved runways).
  5. Better axles.

Hope everyone enjoyed my build log and mini-review. I'll post pics and the video as soon as I get a chance, and will also follow up on how my mods help the plane perform.
Great info....looks like we are starting to get the known issues on the table.
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