The RAT

[flyboyzz1]

Just learned about the RAT as a backup for hyd systems. Anyone have any more info or pictures of one these?

 

[viper548]

It's basically a pinwheel looking thing that drops out into the slipstream and serves as a backup for hydraulics and/or electrics.

 

[AA717driver]

Yeah, you typically test it by standing under the door while talking to someone in cockpit on the headset. You firmly hold the door closed while instructing the guy in the cockpit to lift the guard on the switch and push and hold the switch.












AND... As you are being driven into the concrete you scream--"That AA717driver is a real a$$hole!" TC

P.S.--Hopefully, you will go your entire career without ever having to use or inadvertantly deploying the RAT.

 

[empenage]

http://www.tpub.com/air/7-27.htm

We deploy ours as part of a yearly inspection. Once it's out, its out. And once it's out it's best to break out the David Clarks or Bose headsets because on the Challengers and Global it sounds like someone is running a Cox 049 engine in the cockpit.

 

[empenage]

Yeah, you typically test it by standing under the door while talking to someone in cockpit on the headset. You firmly hold the door closed while instructing the guy in the cockpit to lift the guard on the switch and push and hold the switch.












AND... As you are being driven into the concrete you scream--"That AA717driver is a real a$$hole!" TC

P.S.--Hopefully, you will go your entire career without ever having to use or inadvertantly deploying the RAT.

No kidding, its small but frick'en heavy.

 

[flyboyzz1]

http://www.tpub.com/air/7-27.htm

We deploy ours as part of a yearly inspection. Once it's out, its out. And once it's out it's best to break out the David Clarks or Bose headsets because on the Challengers and Global it sounds like someone is running a Cox 049 engine in the cockpit.

Cool link... thanks! I've heard that many aircraft use the APU instead of the RAT. Why then does the 767 have the RAT if it also has an APU?

 

[BushwickBill]

Cool link... thanks! I've heard that many aircraft use the APU instead of the RAT. Why then does the 767 have the RAT if it also has an APU?

The same reason I would never fly an airbus

 

[dseagrav]

Cool link... thanks! I've heard that many aircraft use the APU instead of the RAT. Why then does the 767 have the RAT if it also has an APU?

They have both because the RAT works without fuel, and the APU doesn't, so you can use the RAT when you have no fuel. On the other hand, the APU works without airspeed, and the RAT doesn't. You can't use the RAT to start the airplane because the first officer can't turn it that fast.

(Two questions arise from this post... One, RAT-turning a job for the F/O or a flight attendant? Two, am I allowed to make jokes like this one even though I don't even have my PPL yet?)

 

[empenage]

Cool link... thanks! I've heard that many aircraft use the APU instead of the RAT. Why then does the 767 have the RAT if it also has an APU?

Engineers are human and have different views like everyone else. A RAT is deployed in case of complete electrical/hydraulic loss in case of emergency, an APU is used for day to day electric and bleed air. Electric to give you light and bleed air to keep you all comfy cozy while your watching The Battle of Britain on the CD player in the back cabin while your waiting for your boss to show up. Once he shows up bleed air is used to start the engines(or electrics depending on the type of starter you have). At this point the APU is shut down untill you land. Then you would start it back up again when you land because soon you are going to turn the engines off and you dont want your boss tripping down the cabin in the dark and falling on the flight attendant.

The GIV has the ABEX (instead of a RAT)system which is a hydaulic pump that runs off the left engine...I hope thats right I havent been in a IV for 4 years.

So...

The RAT if for emergency

The APU gets you started every day.

I need a beer now.........

 

[flyboyzz1]

I didn't mean to use the apu to start the engines. Of course the apu is used for that. I read on a few internet sites that the apu can also be used to run the hyd pump. I don't know crap though.