B737 Panic revision
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Joined: Mar 2003
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From: Seat 1A or 1B
B737 Panic revision
I am in the sim during the next few days; can anyone help with a couple of tech questions for the B737-300 and 500 please.
What does the illumination of an APU BAT OVHT light indicate, obviously a hot battery but is it due to failing exhaust fans or a function of battery charging ? Where are these lights fitted. Forward overhead panel ?
What does the 'Buffet Alert' scratchpad message on the FMC denote, I am supposing a reduced manoeuvre margin but am unable to see this message in any of my FMC notes. The other answer on the question paper describes an upgraded alert called Buffet but I haven't heard of that either.
Lastly, does the ANS alternate nav system have a FDC input or is it solely referenced to the IRSs. I seem to remember that it's just IRS but would be grateful for confirmation.
That's about it, thanks in advance.
Miles Offtarget.
What does the illumination of an APU BAT OVHT light indicate, obviously a hot battery but is it due to failing exhaust fans or a function of battery charging ? Where are these lights fitted. Forward overhead panel ?
What does the 'Buffet Alert' scratchpad message on the FMC denote, I am supposing a reduced manoeuvre margin but am unable to see this message in any of my FMC notes. The other answer on the question paper describes an upgraded alert called Buffet but I haven't heard of that either.
Lastly, does the ANS alternate nav system have a FDC input or is it solely referenced to the IRSs. I seem to remember that it's just IRS but would be grateful for confirmation.
That's about it, thanks in advance.
Miles Offtarget.
Joined: Aug 2006
Posts: 39
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From: Brighton
APU HOT BAT OVHT light – can’t say I’ve ever seen one fitted but I’d guess it either means – don’t try an APU start since the battery is hot and could be damaged. Or more likely, the battery has overheated and charging has been stopped to prevent thermal runaway. On the Elec panel would seem a good place to put it.
Buffet Alert means that your sandwiches are on the way.
No? Sorry. Ok, my notes define the message as “at current conditions, the airplane has a buffet margin less than that selected on Perf Factors page”. The buffet limit envelope is stored in the FMC performance database.
All the ANS systems I’ve seen use IRS unless anyone knows anything more.
Your operator must have picked all the options possible when they brought these.
Buffet Alert means that your sandwiches are on the way.
No? Sorry. Ok, my notes define the message as “at current conditions, the airplane has a buffet margin less than that selected on Perf Factors page”. The buffet limit envelope is stored in the FMC performance database.
All the ANS systems I’ve seen use IRS unless anyone knows anything more.
Your operator must have picked all the options possible when they brought these.
Joined: Sep 2003
Aviation Qualifications: ATPL
Posts: 956
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From: away from home
Don´t remember about the APU BATT, but during my 737 days (3-400) BUFFET ALERT was when you were on the border of the stall protection (1.3G in our case, probably some operators 1.5). When you really get into a buffet situation in a B737 Classic, you won´t miss it.
ANS NAV or Alternate Nav is IRS only, not many operators with this option, but as we flew oceanic in MNPS we needed it to fly without restrictions. Really much like using the old INS.
ANS NAV or Alternate Nav is IRS only, not many operators with this option, but as we flew oceanic in MNPS we needed it to fly without restrictions. Really much like using the old INS.
Joined: Nov 2003
Posts: 496
Likes: 12
From: UK
APU BAT OVHT light is on the aft overhead panel. See http://www.b737.org.uk/electrics.htm
The 'Buffet Alert' scratchpad message means "Current conditions result in a maneuver margin less than specified."
Alternate nav system is purely IRS based. See http://www.b737.org.uk/navigation.htm
There are a few good websites and books out there about the 737, if your company is not providing you with the material (FCOMs) to answer these questions then perhaps you should be finding & bookmarking them.
The 'Buffet Alert' scratchpad message means "Current conditions result in a maneuver margin less than specified."
Alternate nav system is purely IRS based. See http://www.b737.org.uk/navigation.htm
There are a few good websites and books out there about the 737, if your company is not providing you with the material (FCOMs) to answer these questions then perhaps you should be finding & bookmarking them.
