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Comment by Merad | Hacker News Reader

I was under the impression that SOP for most aircraft was to take off at full power, and if you happen to be lightly loaded you just get into the air faster. Was I wrong, or is this a recent change? If so, it seems like a concerning way for airlines to cut costs. Having excess power available at take off means there's a greater margin for error to handle emergencies (engine failure, bird strike, etc.).

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Jets have been using reduced power takeoffs for many decades, with good operational results. There’s an AC about it from 35 years ago: https://www.faa.gov/documentLibrary/media/Advisory_Circular/...

Note that these are manufacturer-sanctioned procedures, not applicable to small piston aircraft, which should be using full power/RPM if the AFM/POH calls for that.

Note also that the full rated power (and sometimes more) is available in the case of an abnormal or emergency.

Everyone else's (consumer's/engineer's/pilot's) "safety margin" is an executive's "cost to be optimized".

Make no mistake. The Exec/finance class will cut into any margin that you aren't willing to make them directly legally culpable for.

Yes. Chelsea Sullenberger ("Sully") made the same point in an interview. He said in the early days of the airlines, the CEO was always a pilot, and error margins were set much higher than legally required. Now that CEOs tend NOT to be retired pilots, new regulations are needed to raise the safety margins beyond current regulatory points to what a safety-conscious pilot would choose.

My understanding is that using less than full power prolongs the life span of engine components and makes fatigue-related engine failures less likely.

Airlines are reducing safety margins in order to do cost cutting.

As long as you save more than $1.5 billion ($5 million x 300 passengers) before a plane crashes, no problem.

Until we completely bankrupt a company for killing people under its jurisdiction, this will all continue.

I'm surprised too. I would have thought the take-off system would incorporate some sort of feedback about how close the tail was to touching the ground and either tell the pilot or correct for it and tell the pilot.

They use reduced power to extend the life of the engines

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