gruntled

It has taken me a while to get this posted, but a couple of weeks ago, the wing of my Shokjet folded in flight. At the time it folded, the plane was flying nearly straight and level. I was not in a high-Gmaneuverand have not yanked the plane around in general and pulled a lot of Gs with it. This happened at a club event in front of 50+ witnesses who can attest to the fact that the plane was not being flown aggressively.

hooker53

My Feedback: (106)

Hey Grunt. That is just sad. I'm sorry for that happening to you. That makes me wanna just take off. fly around and land.

gruntled

Yeah, that sounds pretty good to me about right now.

gjhinshaw

My Feedback: (303)

If I may.... While working at TBM I was there Jet guy. I have had many many jets! Including 5 Shock Jets. Why 5?? Crash!! 2 were caused by putting into a spin. To get out of spin you HAVE to go FULL throttle and UP Elev. ONLY WAY TO GET IT OUT!! 2 were dumb thumd..... No need to explain! 1 was due to turbine taking in lots of water from field puddle. I have never had a wing failure!! I have a Jet Central Falcon cranked to 22 pounds of thurst! I throw this thing around HARD!!!! OK... Saying this and studing the Jet, What I have found in all of R@D was that the wing fails due to the FRONT WING BOLTS not being tight. I know, I know... they were tight..... I have heard it...... But testing the wing I found that if lose it lifts and pulls the front violently! I have learned to tightin the wing bolts tell they don't move. Yes, it is sad due your wing failed but I tell you, I have over 700 flights on the ShockJet alone and no wing has ever failed! I have evan built many for other people and no wing failures. Again it is sad, and I think you can get another for 25% off. I am waiting for the new ones so I may test them!!! Anyway take this for what you think.... If you would like to talk call me. I no longer work at TBM, But you may call.... Gerry Hinshaw 816-528-3544 I will do what I can to help you in the furture!!

gruntled

Nope - wing bolts NOT loose.

phantom_najd

My Feedback: (2)

I test flew my shockjet last week (it's my first jet) and it flew great. It was my first jet flight so I think I was enjoying it because when I landed there were only few ounces of fuel left in the bubble trap (I kinda know now the timer settings).

I landed without flaps and I didn't try to deploy them at high altitudes because I didn't set any down elevator mix with flaps. Can you please tell me if there is a nice point that I can start with? I read somewhere here 15% down elevator with full flaps, can anybody confirm?

Thanks.

Azzam

gjhinshaw

My Feedback: (303)

Thats a GREAT start!! Make sure you have the 2 flap settings. Cross winds I only use first set. Glad you had a blast!! What engine are you using??

phantom_najd

My Feedback: (2)

I sure had a blast. I am using JetCat P-60.

I set up the flaps at 70 and 35 degrees ... I just want to know how much down elevator mix it usually needs when deploying the flaps. Thanks.

Azzam

w4sm

I'm not sure that I have ANY mixed into mine with full flaps. "Your mileage may vary," based in part of weight, CG, etc. You definitely don't need any with "half flaps." Try it at altitude and slower speed and see what happens. With a P60 you'll DEFINITELY need to add power to keep the model flying with full flaps. Other models that I have seem quite variable in how much elevator they need mixed with full flaps, but it's better to have a touch too much down mixed in and have to hold in a little up on approach than to keep pushing down on the stick as the plane approaches!

Good luck and have a blast. The Shok does some of the nicest slow rolls I've ever done.

john491

My Feedback: (13)

At 70deg they will be more like airbrakes. I've got 127 flights and 19 hours in with the ShokJet and a P-60 SE. I use 25-30 for first setting with about 4 deg down elevator. Second flap is about 45-50 deg and uses 6 to 8 degrees of down elevator. Both speeds are set to slow ( about 2 seconds for total movement ) These settings should be tested really high up. When you kick in Flap-1 you don't want any pitch up. When you've slowed a little and kick in landing flaps you want no pitch up either. At altitude you'll be able to see what it does and adjust accordingly when on the ground.
Cheers,
John

phantom_najd

My Feedback: (2)

Thanks guys... I am flying it today again. I will reduce the full flaps setting and will add little down elevator probably between 3-4 for first flaps setting and 7 degrees for full flaps. When I tried landing it without flaps last week with very little power it wouldn't touch down at all then the second approach at idle it took forever to settle (i am lucky to have a very long run way).

I would like to share some pictures. Please tell me if you spot anything that could be a cause of problem in the long run, it's my first jet and I am afraid that I have done anything wrong.



Thanks.

Azzam

gjhinshaw

My Feedback: (303)

GREAT Set-up!! The only thing I see that needs to go is the on board propane tank. If you crash this is what will cause the fire! Just use a one-way festo and you will be good!!

Molar mender

You also have an acute turn on your fuel tubing next to your shut off valve which could leak air in the future. I would wire tie all fuel tubing at the valve and on the fuel pump. I would also get rid of the button stop on the refuel line and place a shut off valve instead. Those stoppers tend to leak air under suction when the pump draws fuel.

Roy

BILLYDSRC

Hi all, This is my first turbine build!! I have built some bigger EDF jets that fly at 20lb. Eveything is done now but the wing. i looked in this tred for for some help putting Robart hinges in the flaps but i had no luck!! Any help would be very nice... Thanks guys Billy D

jblloyd

My Feedback: (17)

I used the CA hinges that came with the plane and have had no problems. I pinned them with tooth-picks just to be sure. They are a lot easier to install than the Robart type.

kb8ife

Great job getting a shock jet I have 92 flights on mine now and flew it out of the box, only add was BVM paint in the turbine area using a super bee, O ya I added real brakes I have some build on here about 840-ish.
have a great time it also dead sticks very good Jim

gjhinshaw

My Feedback: (303)

There is really no need to use the Robart, Unless you just want to.... The CA hinges work GREAT!! Just put them in correctly!!

BILLYDSRC

Thank you all for the help!! I just went with the Robarts in them.Got one wind side done and going to get it all done tonight! I will post some pics of the wing when I et done with it.. Running out of good weather here in Ohio.. Thanks Billy D

gjhinshaw

My Feedback: (303)

Looks GOOD!! May I suggest that you put the Rudder control on the inside. Also I can not see the Elev. control. May I suggest that if you used the carbon rod and ends that you have to glue on, TO THROW THEM AWAY!! Many people have had a problem with them coming apart. On all of my shock jets I us a 4" turnbuckle from hanger 9. Don't worry about the rudder... you can fly with out a rudder but not a Elev.! Now this is JUST my suggestion.

BILLYDSRC

Got eveything ready and went out to maiden it and the wind was 20mph X-wind. Looking like tomorrow will be the day. Here are some more pics Thanks Billy D

gjhinshaw

My Feedback: (303)

Can I make some suggestions??? Or call me and I will Help you.....
816-528-3467
Gerry ( Gary)

Tip22v

I just got my new SJ today, my first turbine. K80F should be here within a week. I have been following this thread pretty closely, lots of good information. I don't know anyone in my local area that is qualified to conduct the turbine waiver training and eval, is there a list posted somewhere by geographic location of pilots willing to help with the waiver requirements?

Thanks,

Tom

rcguy59

My Feedback: (8)

There are quite a few guys up here in the Tacoma area, but I don't know of any down your way. Portland, maybe? If you have a bunch of questions, PM me for my phone #. I have 40 hrs.+ ShokJet time and counting. I've learned quite a bit about this bird and would love to help. I'm not a CD, so I can't give waiver tests, but I'll help in any way I can. A lot of guys up here bad-mouth ShokJets because they're ugly. I like to remind them that while they may be a bit homely, They're GREAT in bed! Let us know when you're ready to start your build (assembly). Mike

jblloyd

My Feedback: (17)

If you go to the documents section of the AMA web site (located in the Members Only section), you can get a complete list of all AMA turbine waiver holders. You should be able to locate someone in your area to help. BTW - love my SJ also.

http://www.modelaircraft.org/MembersOnly/pdf/510-M.pdf

Tip22v

Thanks Mike. I have read through the manual and definitely have some questions, I will pm you. The biggest concern I have is getting the wing due to the problems that have been reported.

Tom