Combat Fuel Shutoffs

Can anyone point me to a picture of a line-tension-loss actuated fuel shutoff of the sort used in combat? (Or a contact if someone is selling them)? I have an idea for a line-tension-loss actuated rudder in speed/racing.

Thanks,
Kim Mortimore

>Can anyone point me to a picture of a line-tension-loss
>actuated fuel shutoff of the sort used in combat?

There's a whole selection of them at http://www.clcombat.info/shutoffs.html

Look at the H&R shutoff, Fourmost's shutoff, Rudner's shutoff, etc.

Thanks, Preston!

LAST EDITED ON Jun-30-03 AT 08:01 PM (CDT)
 
This is a picture of the Huber/Rein shutoff on a speed limit combat ship...

Not sure this will be of any help for a rudder control. Fuel shutoffs should be designed to trigger like a mousetrap, while your rudder control is probably intended to dynamically adjust the rudder, not "failsafe" the flight(?).

Very nice installation. The rudder thing is intended to help with torque roll on takeoff. It isn't a mousetrap trigger, but also not anywhere near as fine-tuned as a Rabe rudder in stunt. Just a crude, keep the thing out of my face idea. On shutoffs that use bellcrank movement in and out, what is the total length of movement? I assume probably less than 1/2".

Thanks!
Kim

Bill Maywald's double bellcrank setup would be of use here. Check out:

http://www.clcombat.info/maywaldshutoff.html

Many years ago, there was a couple of photos of a ratracer in one of the mags. It had a counterbalance weight and was spring or rubber-band loaded to pull the rudder out while at slow speed and then the counterbalance would swing it in at thigher speeds. We never found anything like that to be needed--maybe if we had gone faster?

Fascinating stuff. I especially like the double bellcrank idea. It looks like the shutoff for cut lines requirement stimulated some really creative mechanical engineering. I think finding solutions to technical problems like this is one of the most fun and rewarding parts of the hobby. I appreciate all the replies.

Cheers,
Kim

7/4 Antidedigitization Procedure:
1. Light firecracker.
2. Throw QUICKLY.

LAST EDITED ON Jul-01-03 AT 09:11 PM (CDT)
 
The Shutoff rule is kinda like the BOM rule of Combat. It caused all sorts of arguments and contention, and a lot of people "left" the hobby over it. But with Speed Limit Combat being exempted, and when it became apparent that shutoffs weren't necessarily difficult to use, or impractical, the ruckus has died down of late. As you say, thinking of new ways to shut the fuel off can be fun.

>7/4 Antidedigitization Procedure:
>1. Light firecracker.
>2. Throw QUICKLY.

Anti-mustache removal procedure (I actually saw some idiot do this, once..):

1. Light firecracker (M-80 lookalike) using cigarette in mouth.
2. Quickly fire into air using hand-held catapult.

>This is a picture of the Huber/Rein shutoff on a speed limit
>combat ship...
>
>
>
>Not sure this will be of any help for a rudder control. Fuel
>shutoffs should be designed to trigger like a mousetrap,
>while your rudder control is probably intended to
>dynamically adjust the rudder, not "failsafe" the flight(?).
>
>- Dave

I gotta ask, what does the internal bellcrank,that I see in the
photo, do?.....It appears to be connected to something...
Tony

>I gotta ask, what does the internal bellcrank,that I see in
>the
>photo, do?.....It appears to be connected to something...

It used to be connected to the tailbone..