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German military kicks off heavy lift helicopter competition

reuters.com

11–20 of 67 posts

Re: German military kicks off heavy lift helicopter competition

#11

Same two contenders as the original competition in 1965! Significantly updated but still disappointing in showing how little aerodynamics has progressed in five decades.

The laws of physics have progressed even less since 1965

Re: German military kicks off heavy lift helicopter competition

#12
post #10
post #8

Earlier quoted context omitted.

WTF? I thought aircraft maintenance stipulated that all parts have to be inspected, some often, others seldom, but none never.

A 747-400 has 6 million parts (according to Google). Good luck inspecting all of those.

On each plane it would not be reasonable, but on a few planes it could be done, and would detect defects like the one described above.

Re: German military kicks off heavy lift helicopter competition

#13
post #10
post #8

Earlier quoted context omitted.

WTF? I thought aircraft maintenance stipulated that all parts have to be inspected, some often, others seldom, but none never.

A 747-400 has 6 million parts (according to Google). Good luck inspecting all of those.

During the D maintenance, every part should be inspected. Things like fuel lines should be inspected much more regularly, ideally more often than it would take to rub through a fuel line.

But a visual inspection on a fuel line can be really difficult. I had a motorcycle with a leaky fuel line once, luckily it sprung a leak while warming up in my driveway and I turned off the bike before anything bad happened but it was almost impossible to tell where the leak was without pressurized fuel, the hose looked pristine without positive pressure to highlight the crack.

In race cars, they sometimes 'overpressure' the fuel line (above operating pressure but below max pressure) to check for leaks, I wonder if they ever do that routinely for aircraft.

Re: German military kicks off heavy lift helicopter competition

#15
post #10
post #8

Earlier quoted context omitted.

WTF? I thought aircraft maintenance stipulated that all parts have to be inspected, some often, others seldom, but none never.

A 747-400 has 6 million parts (according to Google). Good luck inspecting all of those.

I believe that B747 do get regularly tear down. They basically remove all the cabins, lots of the conduits and wires, remove the instruments in the cockpit, inspect hidden areas, and reassemble the whole thing.

https://en.wikipedia.org/wiki/Aircraft_maintenance_checks#D_...

Re: German military kicks off heavy lift helicopter competition

#17

Same two contenders as the original competition in 1965! Significantly updated but still disappointing in showing how little aerodynamics has progressed in five decades.

The laws of physics have progressed even less since 1965

Your comment reminded me of https://xkcd.com/1891/

Re: German military kicks off heavy lift helicopter competition

#19
post #3
post #2

The Navy's version of the 53 has a crash rate 3x higher than other helicopters. Maintenance debt killed two of my classmates. https://pilotonline.com/news/military/local/distress-signal-...

A worn-out fuel line had been rubbing silently against a bundle of old electrical wires near the front of the cabin – a problem that had gone undetected for years. The same mechanical defect existed inside every Sea Dragon in the fleet, though nobody knew it. Over nearly three decades, the Navy had never required anyone to regularly inspect Sea Dragon wires or fuel lines for damage. Calling this particular problem ma…

Another statement of treating maintenance & do nothing until it's broken being equivalent.

That is disingenuous.

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