tonystro

My Feedback: (1)

twinman,

Thanks for the post! sounds like you had more fun (??) than you cound 'stand!

'flat' spin is not in my bag of aerobatic tricks. And.. I am definitely not ready to try learning to do one with any of my twins; my hands are shaky without the extra adrenaline!

timrcpilot

My Feedback: (6)

Twinman, I have enjoyed reading about your experiences with this twin ARF.

In one post you mentioned you installed wingtip plates. I am in the process of modifying a twinstar, (similar to Robbie's Phoenix) and am planning on changing out the wingtips to some other configuration, I do not want to use the plastic tips again...

Can you offer any advice or suggestions? Plates? How large? Some other configuration I can build from balsa? Thanks,

Tim

[email protected]

twinman

My Feedback: (2)

The wing plates will add a lot of lift and stability. Knife edge gets easier. I would estimate that the plates should extend 1/2" on such a small plane. Make sure they are the same size. If you are worried about the this concept. Make them of plywood and bolt them on. You will not remove, I am sure.
One way that worked for me. Get a helper to hold the wing vertical over a piece of paper. Using balsa for a spacer to a pencil, follow the outline of the wing completely around, including the ailerons. The tip of the pencil should be 1/2" off the wing to get the correct shape. Using the paper as a template, stack two 3/32" plywood sheets together and cut them out.
Good Luck and let us know how it works for you.
Twinman

Terror Dactyl

Well, Spinman did it this time

We ([8D]The Three Stooges Flight Testing Team[8D]) did additional testing on Sat and with the motor differential set at 100% on the out board motor and 25% on the inboard motor we found that the bird would spin at about 2+ revs per second.

We also found that there is a problem when Twinman howlers to the pits "Can your Twinstar flat spin like that." and you then find out that the bird will not come out of the spin.

The second spin of the flight, Spinman, had it up high and stayed in th e spin (pivoting around the fuse) long enough to starve the reverse rotating engine and then when it was time to come out the motor was dead and provided no thrust to break the spin.

To Spinman's credit he finally listened and pulled the throttle back and tried to save the bird as it finally dropped the nose, but as the spin was so flat and the downward progression was so slow there was no effective air speed left and even with the elevator being applied it still hit mostly nose down.

All things considered it was not that bad a crash and should be back in the air next weekend.

The Three Stooges flight testing team's motto is "We testum and one of us will probably crashum."

More will be following and yes I know that I will catch it for the digs but you dont last long at our field with a thin skin.

BillS

Testing

Once many years ago while managing a Quality Control department the boss suggested that we might possibly develop nondestructive testing strategies instead of destroying everything received from manufacturing. Nondestructive testing was not nearly as much fun. There was always a feeling of accomplishment when a production line could be shut down.

Bill S

twinman

My Feedback: (2)

Bills.
Remind me to never make you mad. This is different. A manufacturer comes to a modeler and loans him a prototype and says test it and let us know what you think.........Yeah!!! Life is good!! This "Modeler" likes to share the "Testing" with some of the more adventuresome types at the field. Not our plane...........yeah!!!! Three heads are better than one.
What we think is happening with the above mix is two fold. The engine on the inside of the spin is only at 25% throttle, which also means no muffler pressure, and two the inside engine is actually rotating backwards, as Rapter said at over 120 rpm. The engine ran and recovered from a short spin time, but this last one and the one the previous week was much longer. This time approximately 30 seconds at almost a hover. We think the fuel is being thrown forward in the fuel tank by the rotation speeds and the engine runs out of fuel in the line. This thing is a blast to sling around the sky and lands like a trainer, but we may have stepped over the line in reliabilty and wanted to warn others of what we think is happening. There is no design fault with the plane, but possibly with what we are doing for the "TEST".
Normally, with this type of induced spin using engine thrust deliberately,(Verses the P-38's), to get out, it is different than our "Single-engine challenged brothers". You do not go to nuetral to get out of the spin, but reverse the rudder and so the engine thrust and it flies out. The mix I use, for safety on the ground, does not affect the engines with rudder until the throttle is above 50%, so knife edge is improved and spins are much easier without special tail weighting. IF YOU TRY THIS...and you reverse the rudder and the plane keeps spinning,,,GO TO IDLE...NOW!!!. It will fall out afer two more spins, due to the high rpm. Nose down, and bring the power back on,using the rudder and ailerons...BOTH. The plane, as previously stated will fly on one engine and loop and roll, but low altitude and coming out of a high speed spin will get the heart rate up.
Isn't this fun???
Twinman

BillS

Twinman your ability to articulate the problem, the cause and the cure is astounding. No one ever gets mad at anyone with those skills.

One might be inclined to ask if the clunk was able to move to the front end of the tank and how much fuel was found in the tank during crash recovery? The shape of the tank might even become a design factor. Over square comes to mind since Spinman is not likely to change his approach to testing.

Thanks for the analysis, which is good press for the manufacturer.

Bill S

PS
Oops woke up early next day with the realization that the tank setup probably cannot be changed. Ignore me.

Terror Dactyl

Oh well, I guess the destruction team will have to continue without me tomorrow as the ugly reality of the job that allows me to afford flying has reared its head and I have to spend the day at work.

Good luck guys and see ya next weekend.

[8D][8D]Now I know that I cant be blamed for any crashing this time either[8D][8D]

BillS

Is it beyond the realm of possibility for TM to spin a story that would imply Spinman was somehow responsible?

We were practicing recovery techniques taught by the master and guaranteed to recover. Spinman was here in spirit and guiding my fingers therefore I knew everything would be OK. At five feet Spinman refused to take the transmitter.

Just wondering.

twinman

My Feedback: (2)

Did you mean Twinman refused to take the controls at five feet???? YOU ARE RIGHT!!!!!!!!.........BUSTED!!!
Twinman

BillS

OK who broke the airplane this time?

With all that throttle control someone should be able to do a full throttle no stall hammerhead on the up line without using the rudder.

Bill S

twinman

My Feedback: (2)

BILLS.
Your killing me............and it was not me.
Up line.........hammer head...........no rudder?......Mmmmm.
Let's see..........uh........Got to go.......uh do something.
Twinman

BillS

Yoyo.
About that no stall hammerhead on a full throttle up line. With your nimble fingers, young eyes and superb responses a yoyo might be accomplished. The turn at the bottom would be tricky but the maneuver would be cool. On the down line kill an engine and throttle up to full and hope the damn thing turns up. Nerves of steel would be required. You can do it.

Bill

JimO

My Feedback: (7)

Pictures at 11, this I would love to have a video of. Have the plane on order so you guy's just keep on testing and when all is done, all I have to do is go fly it. All the Flight testing, structural integrity, and engine set up will be done, and not on my airplane.

Serious thanks for keeping us updated, despite the outcome. Now for the Crow or Harrier????

Terror Dactyl

[8D][8D]And I thought we had some mental health issues at Scobee field, I guess that the three of us are just right in the middle of the group[8D][8D]

As it turns out again I will be spending Sat at the Guglag again, may see ya Sun morning weather permitting

BillS

Terror, to avoid capture all one needs to do is watch carefully and nonchalantly for those in white coats. Normal is a figment of their imitation perpetrated on the unsuspecting.

Bill S

Terror Dactyl

[8D][8D]So that's why TM is always looking around[8D][8D] and my neck is a little sore to. Spinman I guess just fly and to heck with it, wait a minute he is swiveling like the rest of us.

Hope that something got tested yesterday, work reared it ugly head again this weekend and today is rain., oh well

Terror Dactyl

Well here we go again. I can help Sat afternoon or Sunday morning, but the weather is rather liquid both days if you believe the politicans in training.