7 ms·

FYI: that's 85% of the design life of the Continental O-300 engine in that aircraft (1,800 hours time-before-overhaul).

• someweirdperson 4y ago
  Magnetos are time limited to 500 hours.
  • yubiox 4y ago
    Inspection at 500. Not tbo.
• vikingerik 4y ago
  And that's largely why this mission came to an end at this particular duration - the engine had degraded too much from the continuous use, it was barely delivering enough power to stay airborne.
• yunohn 4y ago
  > 1,800 hours time-before-overhaul That’s surprising! Do you mean the entire life of the engine, or just one run? If the former, doesn’t that get expensive? I imagine that’s not very sustainable.
  • evandijk70 4y ago
    In a car running at 100 kph, that would be 180000 km (roughly 110 miles). Most cars would need at least some parts replaced by that time as well..
    • netcraft 4y ago
      I think you forgot the K on your 110K miles
    • stefan_ 4y ago
      Yet only 54000 km at the more typical average speed of 30 km/h. Are aircraft engines typically under high load at cruising speeds? It would seem they are generally overbuilt to overcome the high demands of takeoff.
      • kgermino 4y ago
        I think they are under more of a load a cruising speed than you'd expect. At speed both the car and plane are primarily overcoming wind resistance, which is more about speed and elevation than anything. If I'm understanding right the plane would be going more than highway speed within a few thousand feet of the ground for most of it's (flying) life so it's probably putting more stress on the engine than a car on the highway would. More importantly: if your car engine dies you gradually slow down and pull over. If your plane engine dies calmly pulling over isn't an option. It's much easier to justify spending the money ensuring a plane's engine is reliable.
      • _s 4y ago
        They're generally outputting up to around 75% of their rated horsepower at cruise. I'd say that's closer to going 110km/h or 65mph in 2nd or 3rd gear for most cars.
      • NovemberWhiskey 4y ago
        For example, a typical performance cruise power setting in a Cessna 172SP might be 70% rated power (180 BHP at sea level), which is way, way, way more than you'd ever use for a sustained period in your car. Highway cruising might take 20-40 HP depending on your vehicle, which is probably more like 10% of rated power. 70% of rated power in a typical American car is probably like 120 MPH.
        • idlewords 4y ago
          Also worth mentioning is that they didn't spend all their time on cruise, but had to dip down to refuel from a truck twice a day, putting more work on the engine.
      • sokoloff 4y ago
  • NovemberWhiskey 4y ago
    Overhauling an aircraft engine is a very serious undertaking involving removing the engine from the plane, shipping it away for complete disassembly and replacement of many parts.
  • bitwize 4y ago
    Entire life of the engine. After 1800 hours total operation, the engine should be overhauled: taken apart, cleaned, each part examined and replaced if necessary. Note that per FAA regulations in the USA, only actual flight time counts toward this limit, not time spent taxiing on the ground. It'll take a normal private pilot a few years to reach 1800h of operation, so it's more economical if you're not flying the plane continuously for weeks at a time. But yeah, it's expensive. Owning a plane is expensive. It depends on if it's worth it to you to operate the plane. Small single-engine planes like the Cessna 172 are commonly used for recreation or training. So if you use it often, such frequent overhauls will pay for themselves in terms of safety and reliability. Maybe when all-electric recreational aircraft become common they won't have to be maintained quite so much...
    • travisjungroth 4y ago
      Most private pilots will never get to 1800 hours. Even 100 hours per year is a lot.
    • yunohn 4y ago
      Interesting, thanks for the context. TIL!
      • NovemberWhiskey 4y ago
        Piston engines like you get in a Cessna 172 are also about the worst-case for overhaul times, since there's so much mechanical complexity and because they're often run at/near maximum rated power for long periods. Turboprop engines (effectively these are jet engines with propellers attached) like the ubiquitous P&W PT6A have TBOs up to 4,500 or even 6,000 hours.
        • deepsun 4y ago
          Interesting, I thought everything in Cessna 172 is simple and reasonably forgiving.
          • 4y ago
• m463 4y ago
  is there such a thing as in-flight re-engine-eering?