Welcome, Guest. Please login or register.
Did you miss your activation email?

News:
Precision Simulator update 10.132 (14 February 2021) is now available.
Aerowinx NG FMC and More is now released.

Author Topic: Differences between PSX and 747-400  (Read 343 times)

74pilot

  • Join date: Aug 2009
  • Location: Hong Kong
  • Posts: 61
Differences between PSX and 747-400
« on: Wed, 20 Jan 2021 04:10 »
What is the best way to report inconsistencies? Here, or directly to Hardy?

I just showed the PSX my nephew, and all he was mainly interested in high speed and crashing  ::)

Anyway, with flaps 1 and accelerating, I pressed ALT HOLD, disconnected the A/T and firewalled it. The overspeed warning didn't come on as we went through the overspeed limit and into "the red army". I cleaned up, and kept going. At 365 knots, the overspeed warning came on, just as it should.

Maybe I am wrong (I don't overspeed at work, haha!), but I'd think the overspeed warning should come on any time you even overspeed a flap setting (except for the blowback at F30).

Hardy Heinlin

  • Moderator
  • Join date: May 2009
  • Posts: 12234
    • Aerowinx
Re: Differences between PSX and 747-400
« Reply #1 on: Wed, 20 Jan 2021 04:36 »
What is the best way to report inconsistencies? Here, or directly to Hardy?

Here.

On the real 744 and in PSX, the overspeed alert only activates at MMO 0.92*, not at max flap speed.

Try it in your next sim check :-)


|-|ardy


* If your company refers to JAA instead of FAA, the red MMO tape starts at 0.90 already. But the EICAS overspeed alert still only occurs at 0.92, regardless of the JAA/FAA programming.
« Last edit: Wed, 20 Jan 2021 04:58 by Hardy Heinlin »

74pilot

  • Join date: Aug 2009
  • Location: Hong Kong
  • Posts: 61
Re: Differences between PSX and 747-400
« Reply #2 on: Wed, 20 Jan 2021 07:10 »
Below FL250 or so, it starts around 360 knots. .90 Mach is 595 kts at ISA MSL.

I wasn't sure about the flap overspeed, but since it doesn't do it for F25 and F30, I believe what you say (except that it will trigger what it meets first, 365 KIAS or .90/.92 Mach.

Hardy Heinlin

  • Moderator
  • Join date: May 2009
  • Posts: 12234
    • Aerowinx
Re: Differences between PSX and 747-400
« Reply #3 on: Wed, 20 Jan 2021 08:08 »
Yes, or 365 KIAS, whichever is lower.

74pilot

  • Join date: Aug 2009
  • Location: Hong Kong
  • Posts: 61
Re: Differences between PSX and 747-400
« Reply #4 on: Wed, 20 Jan 2021 14:59 »
Yes, or 365 KIAS, whichever is lower.

I need to overspeed the aircraft more often haha! Or at least the simulator.

An interesting thing on the 747 (and I think, the same on the 737), that the take-off config warning sound is the same as cabin altitude warning (!). It seems very cheap that Boeing couldn't afford two different aural warnings for these things. Yes, you shouldn't get take-off config warning in flight, but it has led a pilot in a 737 to suspect a technical fault, when he forgot the packs (but thought it was a mistake with the take-off config warning system)