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 maintenance debt is a bit disingenuous. PMCS/PMI could have been performed perfectly for decades and not caught this problem. Peculiar dichotomy in this story; the conflation of design flaw and lack of spare parts and improper maintenance.
We shouldn't underestimate what we don't know about building machines. Maintenance should accommodate time to check for wear on parts we don't expect to, to check things that are different from what we expect them to be. The problem was there for decades and one inspection in one unit over that period would probably have evidenced the issue and added one more item for the maintenance checklists.
It's not like the manufacturer can't schedule a full disassembly of a unit 10 years into its lifetime. Car magazines do it.
> It's not like the manufacturer can't schedule a full disassembly of a unit 10 years into its lifetime
Wait hang on, I was under the impression that a D check (?) did exactly this, every 6-7 years. This is second hand knowledge from a pilot buddy so maybe I'm forgetting something. Also it's on the civvy side of things, maybe the military does stuff differently?
If it's as simple as the military has shittier maintenance checks, then that's a solvable problem.
Edit: ok looked it up, it is a civilian vs military thing.
Very little. In this case, a single inspection (assuming all units were affected) over a period of 20 years would have prevented losses that more than compensate the effort of the added scrutiny.
Also, I like to be the first to know I'm wrong. If I make 100 aircraft and dedicate one to disassembly for study after a quarter of its estimated life, I'll be a .75% investment on better understanding my product. If De Havilland had done that, the stress on the square windows of the Comet would have been discovered before they started falling from the skies and we'd all be flying more beautiful planes.
I was shocked when I found out that, in more than 100 flights, nobody inspected the underside or the leading edges of the shuttle in orbit to check for damage incurred on lift off. They were pretty sure the only dangerous part of the flight was the re-entry.
You say a problem does not exist. You may have good reason to think it doesn't, and, yet, people die because it does.
You absolutely should spend time looking for things you expect not to find, because sometimes you will be wrong.
When you're maintaining an aircraft, a nuclear plant, or anything sufficiently complex or life critical, you should spend a certain amount of time looking for ghosts. You _will_ find them. Your model of an engineered system should include a finite rate of unknown bugs.
This was posted here a few months ago. The article indicated that a change/reduction in training starting in 2003, mainly for cost savings, was coming home to roost. I wonder if similar things are going on in the maintenance area.
I'm looking this up now from a sibling comment, I think that yes every N years a civilian aircraft goes through a complete teardown and inspection, taking >50,000 person-hours of time or something depending on the complexity of the aircraft.
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.
So far as the HH-53 (the USAF version), when I rode one in the 80's, the saying was that if it wasn't dripping hydraulic fluid, there was something wrong.
I'm sure they do a thorough inspection, but there is nothing in the video to suggest that they inspect literally every part, or anything close to it. Note that by "every part" I mean every component, not every area of the plane. Your remark about the toilets suggests that you may have assumed the latter interpretation.
Aircraft procedures aren't reasonable. Go and read an accident post-mortem sometime, they're gorgeous. They describe debugging with all the dials turned to eleven. Inspirational.
The reasons planes are so safe is because there are several "unreasonable" things about designing and maintaining aircraft that most engineers would think somewhere between unnecessary and ridiculous.
A lot can be learned from aerospace engineering and the systems engineering used to design air and space vehicles.
Also, a fair amount of the safety of civilian aircraft is because the aircraft owners don't get to skip critical processes, maintenance, etc. They have to answer to regulatory agencies, inspections, etc.
The US military polices itself, so important things can be made optional. They don't have to answer to the FAA on maintenance issues, for example.
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.
If the 6 million parts figure is correct, it's obvious that it is not possible to inspect every part of a 747. Suppose we allow 1 minute per part inspection. Then that's still about 11 years of inspection time (without taking any breaks!)
This is what mature technologies look like. We also had rapid change (and obsolescence) in infantry rifles in the late 19th and early 20th centuries, and one big jump when the assault rifle was adopted, but since then mostly minor changes.
Well besides the political aspect of Germany sourcing key military hardware from what is arguably their largest regional threat, there would also be possible logistical and maintenance issues.
Also switching to Russian Helicopters (The company) and trying to integrate those into the NATO force structure would likely require a great number of changes to be made to the aircraft, which might make them non-competitive on price alone.
not to detract in any way, but Germany was operating Soviet Mig-29s alongside NATO kit for years (maybe still?) after reunification. So if anyone could do it...
It probably depends on the type of equipment they buy, that is, how complex it is and what are the maintenance costs.
For example, Turkey recently declared that they will buy some kind of Russian advanced anti-aircraft system so they probably think that it will be cheaper in long term than buying it from a NATO member. Yet, even in this case they had quite strong tensions with NATO and it is not clear if Germany wants to have (and can afford) similar tensions with NATO, even if these Russian helicopters are technically better.
With the MiG-29s you had the entire former NVA personnel, hardware and experience.
Introducing Russian (or other non-NATO stuff) would require extensive trainings, quite possible new sets of tools, and who knows if any Russian stuff could be made to interoperate with NATO technology.
Not sure it makes sense to buy military aircraft from any given country if being able to stop them from invading you is your military's primary mission.
It depends a bit. For example Finland used to use a lot of Soviet weaponry while (practically if not officially) preparing to deter Soviet attack. Some upsides:
- Results in trade deals with a neighboring superpower
- In case of war, looted enemy armament is familiar and compatible
- Cheaper due to Soviet attempts to keep sphere of influence (e.g. no direct NATO compatibility)
- Making it clear that you're not in the 'other guys' camp.
A NATO Finland would have been incredibly threatening to the Soviet Union. A friendly, non-aligned Finland that just wants to be independent, without stepping on anyone's toes is a useful buffer state.
After the second world war, Finland had to tread very, very carefully.
To add to this comment, the majority of Finland's infantry fighting and transport vehicles that in use are still Soviet BMPs and MTLBs. Same applies to artillery and also all light machine guns are and probably will Russian PKMs for a while.
But yeah since the fall of USSR they've been slowing shifting towards buying from NATO countries/allies, with German Leopard tanks having replaced T-72s and recently buying artillery units from South Korea.
Finland is not a member of NATO and it does not have any foreign army on its territory so it can make a decision based on technical characteristics and economical (not political) factors.
Stopping a major combined arms invasion from an easterly neighbor is the focus of all of Germany's big training exercises to this day. Instead of whatever the Heer says through its public affairs officers, look at what is actually being practiced and paid for with the Euros in the defense budget. It's not counterinsurgency, it's not disaster relief, it's training out of Wildflecken focused on stopping a theoretical invader from penetrating the Fulda Gap with tanks.
"With the fall of the Iron Curtain in 1989, the reunification of Germany in 1990, and the subsequent withdrawal of Soviet forces, the Fulda Gap lost its strategic importance, but it remains a powerful symbol of the Cold War."
Sorry, to be clear, the Fulda Gap is one of the places where they still train. It is no longer strategically important territory the way it was during the Cold War but there is a lot of land available there for ground forces to maneuver.
Agree that, if what they are training for were to actually occur in present day real life, it would likely be in the general vicinity of Kaliningrad.
The Canadian army would struggle to invade a locked Tim Hortons. Germany might not be ready for Barbarossa 2: Electric Boogaloo, but they maintain one of the larger and arguably better equipped militaries in Europe.
the real question would be, why not the europeans?... (EADS (Airbus)).
why not invest into it.
basically I already now the answer. but it's a shame..
(they probably want another disaster after eurofighter/eurocopter/whatever every project where the german governement was directly involved failed, wasn't working as expected... (g36 precision...), or costed a lot more than calculated (not just inside the military..))
> Some officials favor the CH-47 which they say is combat-proven and cheaper, but others say the larger CH-53K would allow growth in future missions.
This implies the 53 is not a combat-proven aircraft....to be clear, the K is just an improved version of the same aircraft that has been operating for like 3 decades.
Hard to see how the 47 would beat the 53, especially if the Germans are actually using the aircraft for heavy lift.
https://pilotonline.com/news/military/local/distress-signal-...