Insane that we can have places like the skunk works create the sr71 and operate on shoe string budgets but the largest passenger plane company in the world can’t accurately assess risk on planes far under the former planes Mach 3 record

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dghlsakjg 2 hours ago | parent | next [-]

Look up the hull loss numbers on the SR-71. More than a third of them were lost in incidents despite never making contact with the enemy.

It was also insanely expensive to operate: $300k/hour in 1990 dollars, and there aren’t reliable numbers on development costs with all of the black budgets.

	▲	tempest_ 2 hours ago \| parent [-]
		33 percent attrition and could only fly once a week. I know satellites and drones have replaced the sr71 but it would be cool if someone would build a plane as capable again.

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mmooss 2 hours ago | parent | prev [-]

I don't see that as a valid comparison. SR-71s could operate with a much higher level of risk than commercial passenger planes. IIRC, SR-71s leaked fuel on the ground, and their wings dragged on the ground without special attachments. Pilots needed special pressure suits, etc.

I also expect that they were much less complex than an aircraft that provides a comfortable, pressurized cabin; the high level of safety mentioned above; freight capacity; etc.

Also, despite Boeing's recent problems, I would guess that commerical passenger planes are far more safe than they were decades ago when the SR-71 was developed. Accidents were much more common despite many fewer flights, iirc.

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imadethis 2 hours ago | parent | next [-]

12/32 SR71s were lost in the 33 years they were flying. 11/200 MD-11s have been hull-lost from 1988-2025. Not to mention that passenger/cargo planes will put on a lot more flight hours than the SR71s did in a given year.

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dylan604 2 hours ago | parent | prev [-]

the SR-71 leaking fuel on the ground was not a design flaw. it was designed to be operated at speed where things would expand to fill in. if they were filled in on the ground, they'd have no place to expand at speed/temps. the risk assessment was that it was better to leak fuel on the ground rather than blowing up at speed/temp

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mmooss an hour ago | parent [-]

Right, it was risk management. I doubt that leaking fuel would be acceptable risk management for a commercial passenger plane at a public airport.

Obviously they could have designed something that could expand and contract if they thought it was worth it.

	▲	lazide an hour ago \| parent [-]
		They designed special fuel that wouldn’t catch on fire under normal circumstances. Also, this was done because airframe skin temps exceeded 400F during flight due to the high speeds.