Tam Jets Gear Fail Safe
#1
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Tam Jets Gear Fail Safe
Anyone know of a another great gear fail safe other than Tam Jets? Not on the Tamjets site anymore.
I go here http://www.tamjets.com/gearfailsafe.phpand click buy it in our store and its not there..
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#3
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RE: Tam Jets Gear Fail Safe
Dan Gill has one at www.Details4Scale.com
Also, Todd at Dreamworks sells the TAM Failsafe and he has developed his own...don't know if it is in production yet but he posted the unit for feedback and pre-ordering about a week ago. www.dreamworksrc.com
If you like Tam's, you might want to call him directly to see if he has them in stock. From time to time, the on line store does not work too well.
Good luck,
Rex
Also, Todd at Dreamworks sells the TAM Failsafe and he has developed his own...don't know if it is in production yet but he posted the unit for feedback and pre-ordering about a week ago. www.dreamworksrc.com
If you like Tam's, you might want to call him directly to see if he has them in stock. From time to time, the on line store does not work too well.
Good luck,
Rex
#5
My Feedback: (61)
RE: Tam Jets Gear Fail Safe
If you need a fail safe and a sequencer this one would be a good choice.
Vin...
http://shopbvmjets.com/zencart/index...o51531obu0cd54
Vin...
http://shopbvmjets.com/zencart/index...o51531obu0cd54
#6
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RE: Tam Jets Gear Fail Safe
This unit also provides sequencing and failsafe: http://dreamworksrc.com/catalog/smar...er-p-1222.html
#7
RE: Tam Jets Gear Fail Safe
Todd, I see it has an "accidental gear up" protection upon power up, but does it lower the gear inflight if pressure drops below a user selectrable pressure? I assume it would?
Ryan.
Ryan.
#9
RE: Tam Jets Gear Fail Safe
If you guys want a simple, very light, reliable, inexpensive, and very effective and controllable way of getting your gear down in the event of an air leak, or total air loss, read the last edition of RCJI. All it needs is an air micro switch, a T fitting, and a non return valve (Clippard items) plus a little tubing. Its a system I designed for my Skygate Hawk and is based on the simple emergency system of several fullsize jets I have flown. It works and can be very easily added to an existing installation.
Regards,
David.
Regards,
David.
#17
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RE: Tam Jets Gear Fail Safe
There is no more "Hard Case" Tamjet units, he ran out of the cases over a year ago. Only ones still available in limited quantity are the shrink wrapped units - At least until the new Dreamworks Failsafe is available, in production now.
#19
RE: Tam Jets Gear Fail Safe
I thought of putting a gear fail safe on my Skygate Hawk but wanted a better system, here's the idea based on the Jet Provost (and F4) system.
The servo which drives the gear valve can contact an air micro switch when it over travels slightly from the gear down position, the over travel being created by mixing gear to gear on the radio. No servo or channel required. The air supply to the micro switch is either the brake tank or a separate air tank. When the micro switch opens the air from this tank is fed to the valve via a T connector In the supply line but is prevented from returning to the main tank via a NRV inserted in the supply line upstream of the T. It's that simple.
So if your gear doesn't extend when selected down operate the mixer switch and feed alternate air to the valve at the pressure in the reserve tank. Down comes the gear, simple. !
If you have an electronic gear valve use a micro servo Y,d into the channel to operate the micro switch.
If you have air driven doors, supply this valve too with alternate air, if you wish.
If desired, instead of using the brake tank, use a separate air tank.
The advantage of this system is that YOU choose when to extend the gear, even after the original leak which is almost certainly in the UP system.
You also extend the gear with full pressure in contrast with a lower, depleted pressure.
It is tested by retracting the gear, then clamping the main supply hose and then trying the ALT system, simple.
I believe this is a more controllable and potentially more reliable system than an electronic faisafe, less than half the price, too.
Regards,
David.
The servo which drives the gear valve can contact an air micro switch when it over travels slightly from the gear down position, the over travel being created by mixing gear to gear on the radio. No servo or channel required. The air supply to the micro switch is either the brake tank or a separate air tank. When the micro switch opens the air from this tank is fed to the valve via a T connector In the supply line but is prevented from returning to the main tank via a NRV inserted in the supply line upstream of the T. It's that simple.
So if your gear doesn't extend when selected down operate the mixer switch and feed alternate air to the valve at the pressure in the reserve tank. Down comes the gear, simple. !
If you have an electronic gear valve use a micro servo Y,d into the channel to operate the micro switch.
If you have air driven doors, supply this valve too with alternate air, if you wish.
If desired, instead of using the brake tank, use a separate air tank.
The advantage of this system is that YOU choose when to extend the gear, even after the original leak which is almost certainly in the UP system.
You also extend the gear with full pressure in contrast with a lower, depleted pressure.
It is tested by retracting the gear, then clamping the main supply hose and then trying the ALT system, simple.
I believe this is a more controllable and potentially more reliable system than an electronic faisafe, less than half the price, too.
Regards,
David.
#22
RE: Tam Jets Gear Fail Safe
Here's a picture of my system. Here the servo is in the normal gear down position, valve open but the servo is not contacting the micro switch, triggering a slight override by mixing gear to gear opens the air micro switch feeding standby air to the selector valve. In this layout I have used a separate tank (you could use the brake tank) and fill valve plus a guage. The normal supply line is the blue line, the standby air is T'ed into it but can't pressurise the main supply tank because of the one way valve in the line. This system is going into all my large jets.
Regards,
David.
Regards,
David.
#23
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RE: Tam Jets Gear Fail Safe
David,
Thanks for sharing.
What if the button valve leaks? You could lose all primary and secondary air couldn't you?
I had a problem with that valve once, granted it leaked when not fully depressed..
I have had my A10 saved by tam's device and will continue to put some kind of backup in, at least until we go electric!
Dave
Thanks for sharing.
What if the button valve leaks? You could lose all primary and secondary air couldn't you?
I had a problem with that valve once, granted it leaked when not fully depressed..
I have had my A10 saved by tam's device and will continue to put some kind of backup in, at least until we go electric!
Dave
#25
RE: Tam Jets Gear Fail Safe
Yes Dave you are correct so belt and braces may be the way to go. That said I have always had complete success with Clippard units and the rare leakage problems I have had have been internal cylinder seals in the retraction pistons which would be handled by my system.
Now you have raised the issue (thank you !) I will protect against the leak you suspect by inserting a one way valve in the line between the T and the micro switch. Should solve that problem as you would need a simultaneous leak in two components, both the NRV and the micro switch before you lost all air, extremely unlikely. ( By the way in this shot the hoses on the switch are transposed.)
I have had an air micro switch on the nose gear door of my. BVM F4 which is actuated on every flight by the nose leg which signals all doors closed, still working perfectly after 12 years.
I guess nothing is absolutely certain as discovered by the captain of the Polish Boeing 767 when both his primary and alternate gear extension system failed and he landed wheels up at Warsaw !
Regards,
David.
Now you have raised the issue (thank you !) I will protect against the leak you suspect by inserting a one way valve in the line between the T and the micro switch. Should solve that problem as you would need a simultaneous leak in two components, both the NRV and the micro switch before you lost all air, extremely unlikely. ( By the way in this shot the hoses on the switch are transposed.)
I have had an air micro switch on the nose gear door of my. BVM F4 which is actuated on every flight by the nose leg which signals all doors closed, still working perfectly after 12 years.
I guess nothing is absolutely certain as discovered by the captain of the Polish Boeing 767 when both his primary and alternate gear extension system failed and he landed wheels up at Warsaw !
Regards,
David.