Real Answers from Real Pilots

Minimums on departure?

Hi,
The other day I visited a 737 cockpit before departure and for some reason realized the minimums were set about 1000 feet above the airfield, is this the minimums from the previous flight? Or do you have any minimums depating,
I know this question may be strange but I am just curious :joy:
Thank you,
Martin

Martin,

Not really sure what you were looking? There are no “minimums” that get set for takeoff? (There can be takeoff minimums but they’re not “set” anywhere). Prior to landing the DA (decision altitude, or DH decision height) or MDA (min descent alt) will be set but they’re rarely that high and are usually reset and don’t appear for takeoff. That said I’ve never flown a 737 so maybe there’s something there I’m not aware of? Chris?

Adam

The minimums were set on the DH knob :thinking:

Then perhaps they were from the last flight but and the crew hadn’t reset them yet. Again 1000’ above field is unusually high.

Adam

Martin,

Every airline’s procedures are different, but on United the minimums bug is set for the single engine acceleration altitude. This means that should you lose an engine on takeoff or initial climb, this is the altitude where you will reduce the climb rate to a very nominal rate (say 100 feet per minute) to accelerate the airplane and clean up the flaps. Until that point we are flying at a speed that while slow, maximizes our climb rate to get away from the ground. Needless to say, airplanes do not climb very well on one engine.

At United the “acceleration altitude” is usually 800 feet above the ground, but can vary with the terrain in the area.

I am happy to answer your questions, but feel feel to ask your pilots next time you visit a cockpit. Most of us are always happy to talk with passengers and explain things, especially to a future aviator.

Chris

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Oh alright that makes sense, it was a United aircraft, thank you for your answers :grinning: