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When you file a flight plan from Oakland to Honolulu
you put "Glory" as your alternate destination.[1]

Is that the correct way to file the flightplan?

Scanning back a few paragraphs, the airplane in question was a Cessna 402.

[1] B. May, Under His Wing: Adventures in Trusting God, p. 40 (Multnomah Publications, 1991. ISBN 0-930014-94-4.)

Please note while the publication is 1991, the actual copyright is 1979, so we are looking before that date.

J W
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Joshua
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    Can you clarify the context and what it is that you're asking exactly? – abey Jan 04 '15 at 02:45
  • I'm suspecting at the time of the incident there was only one airport in Hawaii, or alternatively there really aren't alternate destinations that are likely to be any better off. – Joshua Jan 04 '15 at 03:14
  • @Joshua Hawaii was a significant location for the military during World War II: there were plenty of air fields there. What are now Hilo and Honolulu International Airports both opened in 1927. – David Richerby Jan 04 '15 at 12:15
  • So anyway I'm not sure how to reword the question; however the correct answer is certainly spread between Davis Richerby's comment and Mike Foxtrot's answer. I'm ready to conclude overwritten for effect, but essentially true. If trouble a long way over the water, if cannot make Hilo, doomed. – Joshua Jan 04 '15 at 20:59
  • I'm not sure exactly how to plot a great circle route; however I'm pretty sure Hilo is not much closer than Honolulu. – Joshua Jan 04 '15 at 21:01
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    @Joshua You can plot a great circle route at gcmap.com. Also, there are more airports in Hawaii than just Hilo and Honolulu. Also also, you need an alternate for reasons other than failure of your own plane. The weather at your intended airport, or an incident there may force you to land your perfectly working plane somewhere else. – David Richerby Jan 05 '15 at 09:21
  • @DavidRicherby, would the weather not be the same as ALL airports within range of Hawaii? – Ian Ringrose May 26 '16 at 10:48
  • @IanRingrose Not at all. Hawaii is mountainous and 400 miles long. As a simple example of the variability of its weather, Honolulu receives 3,000 hours of sunshine a year and 430mm of rain, whereas Hilo gets 1,800 hours of sunshine and 3,200mm (sic) of rain. – David Richerby May 27 '16 at 14:36

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There are plenty of alternative airports in Hawaii, but none in-between of course. So what the author is getting at is that you're probably going to be dead if you run into trouble.

While I can't say I know anything much about the Cessna 402, it apparently has a normal range of around 1,273 nm (1,467 mi, 2,360 km), compared to a distance Hawaii-Oakland of 2050nm (2359mi, 3797km). Hence, you're going to have to install additional fuel tanks and fly pretty heavy.

There a few considerations if you get a problem:

  • You will have to descend since the engine can't generate enough thrust at that cruise altitude. I found a source stating the ceiling for both engines is around 26180 ft compared to 11320 ft for one engine.
  • The fuel consumption increases in the remaining engine and will be greater than the total for both engines for the same flying conditions.
  • You're going to have to run the remaining engine hard for the remain of the flight.
  • If your temporary ferry tanks screw up (or any of the normal ones for that matter as well), you won't make it.
  • You may damage/break the gear if you have to return to the airport overloaded. "I once saw a Cessna 402 parked on the ramp at Honolulu with the gear punched half way up into the wings from a poorly executed overweight landing." Source

I can't do a calculation on for what portion of the flight you would be 'screwed' but I imagine it might very well be a bit of the journey. Several people seem to be in the opinion it's a pain to fly heavy and difficult to with one engine.

Thunderstrike
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  • Well the book is really scant on details, but it mentions an extra ton of fuel. – Joshua Jan 03 '15 at 22:20
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    The good news, as I recall, is that there are headwinds to the halfway pint, and favorable winds on the second half. – rbp Jan 04 '15 at 00:08
  • Another bit of trivia is the Bob Hope lived in Hawaii and flew back and forth in his 4-engine JetStar – rbp Jan 04 '15 at 00:12
  • The first two points should be in reverse order. Developing the same total power with one or two engines needs about the same amount of fuel. It is the lower ceiling that causes the higher fuel consumption, because there is more drag at lower altitude and thus more power is needed. – Jan Hudec Jan 05 '15 at 19:15
  • @JanHudec although I'd agree that it's not a huge difference, one engine at higher power is usually less efficient (in terms of miles per gallon, not gallons per hour) than two running at lower power, simply due to the lower speeds involved, producing less waste to heat/noise. – Jon Story Jan 06 '15 at 12:03
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    @JonStory: For pistons, slightly yes. For turbines, however, definitely false. Turbines (both prop and jet) are most efficient at their maximum power. – Jan Hudec Jan 06 '15 at 13:37
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    @JanHudec I haven't seen many jet powered Cessna 402's though.... – Jon Story Jan 06 '15 at 13:47
  • @JonStory: Of course. Still the need to fly lower is and the corresponding higher drag is the larger part of the reason why more fuel is used, even with a piston engine above it's most efficient power range. – Jan Hudec Jan 06 '15 at 13:48