That is a great idea.  Thanks.

Twins and retracts.  I'm so far behind.

When the wheels go up
Scores should erupt
But they’ll say I’m a clown
If they don’t come down

If the judges were managing to be completely objective, retracts would only make a difference in as much as they affect the aerodynamics of flight (and if they make it worse -- oops).  I suspect that if you get any points from the "wow" factor, it'll wear off as the judges get used to seeing the wheels go up.

I'm sure you're already thinking about this, but it sure seems that you'd want to think carefully about when you want the gear to go up.  Too soon and the "wow" factor is of entirely the wrong kind.  Too late and you don't get nearly as much "wow" as you'd like.  Just right, from a purely aesthetic point of view, would be to start a slow retract right as the wheels leave the ground -- but that really flirts with 'too soon' if anything delays takeoff.

I'd be concerned with the retracts messing up the airflow when I'm trying to achieve a smooth takeoff and level flight (actually, I'm a rank beginner -- I can't reliably achieve level flight yet, so retracts would just give me something to blame other than myself).  At worst, you could time things so that the wheels went up after your two laps of level flight, but that would certainly remove a lot of the "wow".  At best, any bobbles from the wheels going up would be slow, and could be timed for the climb phase of the takeoff where they'd hopefully get subsumed in the overall climb.

I should introduce you guys.  Bob, meet Tim. Tim, Bob.  Bob is a former US National and World stunt champ.  He also either built a good chunk of our airplanes or taught us how to do it ourselves.  Bob is a good guy.  Tim is an electrical engineer who does motor control systems for a living.  We are learning things from him, too.  Tim is also a good guy. 

It sure seems that with a wide selection motors and props, that you should be able to get more braking in he down lines.  You may need to go with some combination that's too aggressive at braking when the gear is down.

And I didn't want to say anything that would stop you: I'm just mentioning points that you may have not yet pondered, or have skipped over lightly.

Since that experience in 1976, Bob pioneered tuned pipes in stunt planes.  Now he's known for having one of the best regulated electric powerplants.  He'll be OK if he doesn't get the polarity on the props and motors mixed up:

motor 1 rotation   motor 2 rotation   prop 1  prop 2  outcome
        L                       L                  L         L         OK
        L                       L                  L         R         bad
        L                       L                  R         L         bad
        L                       L                  R         R         bad
        L                       R                  L         L         bad
        L                       R                  L         R         good
        L                       R                  R         L         bad
        L                       R                  R         R         bad  
        R                       L                  L         L         bad
        R                       L                  L         R         bad
        R                       L                  R         L         good
        R                       L                  R         R         bad
        R                       R                  L         L         bad
        R                       R                  L         R         bad
        R                       R                  R         L         bad
        R                       R                  R         R         OK

I wouldn't risk it.

Actually, Bob is just covering up our efforts at creating the first Stealth Heli-Stunter.

In a semi-reenactment of Bob and Jim Hunt's efforts back in '76, I created a one-off control system that would control retracts via the lines but without having to insulate them. We called it FRED for Functional Retracts Eliminate Drag.
Right after Toledo in '89, I drove to Werwage's place and we spent 36 almost nonstop hours cutting retrcats into his old Tiger 46 powered Blue Max (really just another USA-1). Cutting Retract wells into an I-beamer was a joy! A few weekends later Bob, Bill and i flew the ship in turbulent air and the results were similarly astounding. We never had runway wind conditions to fly in, and the entire program was put on the back burner before they were available.
Regards,
Dean P.

Personally I expect great things from your current effort.

But you know how Bob gets hot when his current effort meets with resistance.

 Watt's up Bob?

Dissapointing... I wonder If its too late for me to refund me airline ticket......


I thought the crossfire was at the same stage of finish?

It seems that everybody wants a Motorcycle License to allow them to buy a small and fuel efficient bike for commuting and for errands. That's actually a very bad reason to buy a bike...

I sometimes consider buying a motorcycle for just that reason, then I reflect on the fact that I have totaled not one, but two bicycles by rear-ending cars and I change my mind.

I doubt that I'll make it to the nats before your twin is worn out, so when you get it flying would you please post a movie or two -- maybe one walk-around, and another flying?

I sometimes consider buying a motorcycle for just that reason, then I reflect on the fact that I have totaled not one, but two bicycles by rear-ending cars and I change my mind.

You need to put a front brake on your bike ... and learn how to use it

There's a reason why cars and motorcycles have bigger brakes in the front 

 It's been quite a while Bob, what's the latest???

"I plan on starting on it again sometime later this month (September)"


Well ? Updates... we need updates.....

27 Sept..

The Crossfire refinish looks wonderful!

Will you be in Muncie next week? 

Jason

Looks fantastic Bob!!! Best of luck with it next week at the NATS!

Wow, the twin's gear installation is some kind of cool.  
The only thing that could top that would be full funcioning gear doors. (but I wouldn't even think about going there).

Hey Bob:
  
What is the setup of the thrust lines on the twin,  motors and stab relative to the wing ?

Are you going to setup the motors counter-rotation ?    If so, what props are you thinking about ?

Sorry if these have been covered earlier.  If so, let me know and I'll go back and re-read the whole thread.

Now how are we going to know which is Bob's planes?     Really Bob, the scheme looks great.   Have fun at the NATS and don't be too hard on the kids.

Derek, you could learn alot from Bob - those wheel pants came out of his workshop that way the same day the model was painted.

 

HI Brother Bob!

The refinished Crossfire does look awesome.  And the Second Wind is coming along.  I believe it will be very competitive once you work into it.

A thanks from us all for your tireless efforts to make this hobby/sport a better place.  And good luck in Muncie!

Bill

Bob - did you fix that tracking error with the rebuild?

Awesome....

Randy and I both went through total refinishes..... they are hell.

I wont do it again - and I've done 3 of them.... problem is you *think* it will be easier than it is.. despite doing it before..

That is awesome.   Start a new trend in electric and leave in in clear or primer.

Hi Bob,

I wonder if you are planning on counter-rotating, two pusher or two tractor props. If you are doing counter-rotation which is going to be which?

Thanks and OH yes it looks awesome so far!

Hurry up and finish it, I want to see that thing fly!!! 

Looks awesome Bob.

Derek