Even though I save the file with the Fuel Cut off levers in the Cut off position. Every time I select the aircraft they are turned back on. Is there something in the aircraft.cfg that can prevent this or am I doing something wrong ?Kind regardsNigel Thomas-Smith

There are various button/switch states that do not survive a save/load at the moment. This is one of them...ray

Oh well, it's sometimes nice to have a switch or two to flick when doing the pre-flight !Incidently, what would happen on a real aircraft if it was left in this posistion. (Say they, or one of them was moved when the aircraft was on the ground by some careless guy around the cockpit area - Pilot that is, engineers never do things like that :) Guess, it would have no consequence unless there was an attempt to start the engine with the valve open.Any guys out there ever done it. Don't think it's even in the Boeing handbook. That allways seems to assume that we never make mistakes and never gives an example of what one should have to do if things were carried out in a wrong sequence - Guess it would be even fatter than ever to cater for all those permutations.Have a nice flight yer all.Nigel Thomas-Smith

Entered in error. More thinking to do.Cheers.Ian

I can only speak for the CFM engines we have on our A320 fleet but it is the same core engine as the 737 fleet so it should have a similar system. On the A320, turning on the fuel control switch with the engine shut-down and no Engine Driven Fuel pump pressure won't do much of anything since the Fuel control shut-off valve requires fuel pressure to operate. Unless the Engine Driven Fuel Pump is producing at least 300 psi it will not open the valve. Ian, May we have additional Details Please :-)Paul Gollnick :-coolTechnical Operations/Customer Operational SupportPrecision Manuals Development Groupwww.precisionmanuals.com

"Ian, May we have additional Details Please :-)"For a minute there, Paul, I forgot which site I was on... and started talking about the "AUTO" ignition switch (on a 767 :-lol)... Hence the rethink."Incidently, what would happen on a real aircraft if it was left in this posistion. (Say they, or one of them was moved when the aircraft was on the ground by some careless guy around the cockpit area -"Interesting question, Nigel.My first impression is this, but I may have overlooked some fuel/ignition logic...On a windy day, a windmilling engine, I believe, has the potential to suck fuel from the tanks...or at least drain the fuel from the fuel manifold (distribution pipes) in the wing and engine area.... and dump it into the engine combustion chamber. As Paul has just said, a certain fuel pressure may be required to get the fuel into the chamber. I really don't know what engine/pump rpm would be required to do this. You may require hurricane force winds to generate the rpms required, you may not(???). However, on other aircraft, I have been told (by a reliable source) that on hot days, you may get large enough fuel pressures building-up in certain sections of the engine fuel system to force the fuel into the combustion chamber, even when the engine is not windmilling.Anyway, when the Fuel Levers are placed in IDLE, the engine EEC's (fuel/ignition controllers) are powered-up (BTW, you can tell the EEC's are powered when all the engine parameters are visible on the EICAS screen). The EEC's have the potential to command the engine ignitors to fire causing the fuel to burn.With the aircraft sitting on the tarmac with the Start Switch in OFF, there doesn't seem to be too much risk (of an EEC-sourced spark generating a fire), but on normal engine start (or if the Start Switch is put into a position other than OFF for maintenance purposes), a spark will/(may) be generated and this plus the fuel build-up in the combustion chambers may cause a fire. Normally the 737 has "hot start" protection (it will shut off the fuel supply if the EGT's get too high during a normal ground start, but I doubt it could stop the pooled fuel already in the combustion chamber from burning. The combustion chamber is designed to withstand high temperatures, but it may still do some damage).There is some logic I'm not familiar with which may cause the EEC to signal the ignitors to fire: "(If the) engine start lever is in the IDLE position (and) the engine speed decreases uncommanded.... both ignition systems are energized for 30 seconds".I think I would need more details on EEC operation before I could tell you what engine parameters/switch positions are looked at for the EEC to determine whether or not an uncommanded speed decrease is taking place.Anyway, hope this helps.Cheers.Ian.

HeheheheI knew he would have the details :-lolYour hot start reminds me of an interesting story I was witness to some years ago. After replacing the Fuel Control unit on a 747-400 the Technicians were on board preparing to start and taxi to a run up area to perform the functional checks. Upon starting the recently repaired engine the Fuel Control went to a Full T/O thrust configuration dumping over 12,000lbs per hour FF into the engine during the start cycle. :-eek Needless to say this created quite an interesting spectacle on the ground with flames shooting over 40 feet into the air (after burning off the Aft Flap) Back to the barn :-doh Problem was traced to shorted Servo inside the Fuel Control somehow missed by the Shop during overhaul. :-dohPaul Gollnick :-coolTechnical Operations/Customer Operational SupportPrecision Manuals Development Groupwww.precisionmanuals.com