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What's not allowed any longer?
- Thread starter fyrwrxz
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90%+ of accidents are caused by bad implementation by the modeler, or human error. Very rarely the hardware method.
If you "ban" every method that ever causes an accident, you'd pretty much have to ban every electronic method as well as some other pyrotechnic & mechanical methods (Hey, put a dua deploy altimeter deep down inside of a body tube, with the power inside the tube. Put your arm inside to arm or disarm it, and "poof". Yep, really happened, burned arm, not the altimeter's fault)
And yeah, if the need arises for something simple where suitable, I'll dig out an old-school thermostat style mercury switch, be sure I implement it properly, and treat it with care for the arm and post-arm process.
My Space Shuttle that has a flight computer to sep the SRB's and fire ejection in the ET after it detects the orbiter is gone, or 6 seconds after liftoff (whichever is first, in case of orbiter not sepping), detects liftoff, to start the active in-flight program sequence, by this simple method:
It has a short 1/8" rod mounted to the pad, going inside the ET base to press onto a lever switch. When it moves up about 3" and the lever is open, it detects liftoff. I'll wait for some to yell what is wrong with doing liftoff detect like that. Then I'll post the simple (well, sort of simple) safeguard to prevent false liftoff detection. As indeed, by itself, that is dangerous, but it would be totally stupid for anyone to BAN it for using that method despite the fail-safe that totally solves it.
If you "ban" every method that ever causes an accident, you'd pretty much have to ban every electronic method as well as some other pyrotechnic & mechanical methods (Hey, put a dua deploy altimeter deep down inside of a body tube, with the power inside the tube. Put your arm inside to arm or disarm it, and "poof". Yep, really happened, burned arm, not the altimeter's fault)
And yeah, if the need arises for something simple where suitable, I'll dig out an old-school thermostat style mercury switch, be sure I implement it properly, and treat it with care for the arm and post-arm process.
My Space Shuttle that has a flight computer to sep the SRB's and fire ejection in the ET after it detects the orbiter is gone, or 6 seconds after liftoff (whichever is first, in case of orbiter not sepping), detects liftoff, to start the active in-flight program sequence, by this simple method:
It has a short 1/8" rod mounted to the pad, going inside the ET base to press onto a lever switch. When it moves up about 3" and the lever is open, it detects liftoff. I'll wait for some to yell what is wrong with doing liftoff detect like that. Then I'll post the simple (well, sort of simple) safeguard to prevent false liftoff detection. As indeed, by itself, that is dangerous, but it would be totally stupid for anyone to BAN it for using that method despite the fail-safe that totally solves it.
Rocketjunkie
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Before 1995 when the 3 level certification process was implemented, all you had to do was fly a H to 'confirm'. I flew an H, later that year I flew a K and the following year an O in 1990. In 1995, all 'confirmed' members were L1 and had to do L2 and L3.
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Well, FWIW - here's the safeguard. The shuttle's engine mount was designed to let the engine slide about 3/16" of an inch. At ignition, the engine presses on a lever switch, or "thrust" switch. If the Flight Computer sees thrust, and then liftoff, then it is a valid liftoff and the programming goes onto the next step. If the computer sees "liftoff" but no thrust (If I stupidly raised the model up the rail while armed), it beeps an error code and stops, because there can't be a valid liftoff without engine thrust.
But if I flew that at a field where the RSO had it burned into his brain that a liftoff detect switch was BANNED, regardless of implementation or safeguards, it would be absolutely ridiculous.
I had one of those in my old CJ-5 (1974 model - last of the solid frames with factory 5 speed transfer case and factory Dana 44 rear end)
Man, that thing would climb a tree if it could get traction
