On modern jets, because of safety regulations, there is only one thing a pilot can do to shut down an engine... That is, stop pouring fuel into the engine. You can't stop an engine by switching electric power off. In fact, you actually need electric power to shut down an engine.Normally, the power to do this comes from the Hot Battery Bus (28Vdc power is always on this bus, either from the main elec busses or directly from the Battery, but you don't have to have the Battery Switch ON to get power to this bus). By putting the fuel lever to CUTOFF or pulling the Fire Handle, you are activating an electric circuit to shut the engine fuel supply valves. Unfortunately, there was an incident with a 747-400 which ran off the end of a runway and ended up nose-down in the ocean... which happened to be at the end of the runway. The Main Battery on a 747-400 is located in the lower part of the nose and, in this situation, was probably underwater... and was no help in shutting down the engines. It took firemen a l-o-n-g time to extinguish the engines using their hoses. I believe, as a result of this incident, FAA insisted that all new aircraft types have a back-up supply of power to shut down their engines. The 777 and our beloved 737NG has one of these back-up power supplies. In the case of the NG, it is located right behind the F/O in the cockpit. It is a rechargeable power supply and can provide power to shut down the engines even if the Main Battery has gone flat.That's something new I learned today :-)So even if you don't have FSUIC installed to stop your battery going flat... don't worry, you can still shut down your engines ;-) However, if the back-up power supply isn't modelled in PMDG, you may have to wait for the firemen (sorry... "firepersons") to arrive...or until your fuel tanks are empty :(Cheers.Ian.

Thats very imteresting Ian. Thanks.Also you cant go wrong if instead you just use Fire Fighters rather than Fireman. Then you wont insult any gender.:-lolAndrew

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Very interesting, Ian. Thanks for sharing it!Bruno Francescoli.

Hi Ian,I have a slightly off-topic engine shutdown question that perhaps you can answer. I have always wondered in the back of my mind if the fuel cutoff levers have some sort of locking mechanism to prevent accidental inflight shutdown? It seems to me that it would be really easy to snag your shirt sleeve on them or knock into one while reaching for something and shutdown an engine accidently.If there is no locking system, has this sort of thing ever happened that you know of?Thanks,Jeff

Yes, this has happened in the past. There was a United 767-200 that flamed out after the Captain shut off the fuel climbing through 3000 feet. (They'd have had to dry-clean my seat!).Engines were restarted and airliner returned to SFO.The official cause had to do with Pilot Impairment.You can look up the NTSB report at:http://www.ntsb.gov/ntsb/brief.asp?ev_id=2...213X33116&key=1

Interesting...I'll give it a quick read. I noticed you said Engine_s (plural). I would assume he got a RAT deployment? What a nightmare...I would probably hang up my hat after that (if they didn't do it for me :) ) Jeff

As "CapnLars" says, this has happened before. Sometimes there are guards on either side of the levers to help prevent this happening.Normally, important switches have a (strong) spring and (deep) detent system to prevent accidental operation, but wear and tear sees these reduce in effectiveness over time. The move to rounded fuel shutoff levers may have reduced the likelihood of this happening. The 737NG seems to have retained the old L-shaped levers, however. Perhaps there is less risk of hooking these because they are so close together (with their L-shapes forming almost a closed loop).http://members.ozemail.com.au/~b744er/737/NGCutoffLevers.jpgHope this helps.Cheers.Ian.

Yes it was BOTH!I was told (not verfied by independant party) that a cabin announcement was made beginning with something like "You might be wondering why it's so quiet back there.....".Larry

gotta say I really love your photo shot Ian. They are very unique and just not the standard panel shots. Reminds me of the ones over on the PS1 site that H took of the 74.It makes it real, brings depth to the usual panel shotsthanks