13
$\begingroup$

Two years ago I flew from Tel Aviv, Israel to Tromso, Norway via Riga and Oslo. The Tel Aviv-Riga leg was flown in an A320, and the Riga-Oslo and Oslo-Tromso legs were flown in prop planes, Fokker airplanes I think.

What considerations are used to determine what type of plane will fly for a particular journey?

Obviously the choice would be limited to whatever aircraft the carrier has available, but given reasonable choice of any aircraft that seats the required amount of passengers, what considerations are used to decide on props or jets? Runway size? Fuel efficiency for short / long trips? Weather or temperature (both current and typical)?

$\endgroup$
12
$\begingroup$

This question devolves into two related questions.

1) When buying or leasing the plane, what is the most economical plane for this route (and other routes that the plane may have to fly) at your airline. One size does not fit all, what is optimal for one leg may be much less desirable for the next. "Economical" includes capital costs, maintenance costs, operating costs, and down-time costs. Are your maintenance facilities proficient on this type plane? Are your pilots cross trained on this new aircraft?

2) Years later your short term choices are limited to the aircraft in your inventory. What is the best available aircraft for this flight? For the entire route? Can this plane fit into the runways at the required airports? Can the aircraft make the trip without stopping for fuel? How many passengers have booked this flight in advance? the questions that need to be considered are many.

Short answer: "Oh, I think I'll fly the Turboprop today" is not how it works. It is a long involved decision considering multiple factors all leading to what user16230 calls efficiency and what I will call profit. Same thing measured differently.

$\endgroup$
  • 3
    $\begingroup$ This doesn't really answer the question of "what factors make a turboprop more efficient than a turbofan?". Or to put it another way, aren't turbofan "jet engines" better for everything? Clearly they aren't, because smaller planes don't always use them. Not to be too negative, but your whole answer is basically "because economic reasons". For curious noobs like myself that don't know the design considerations, it's not helpful since I already figured that part out on my own. :/ I guess I'll just up-vode user16230's answer, since that's the kind of thing I was looking for. :P $\endgroup$ – Peter Cordes Mar 25 '15 at 8:25
17
$\begingroup$

I believe this question is answered here and a nice comparison can be found here but the short answer is efficiency. If memory serves jets gain their efficiency at high altitude moving fast and generally over a long distance. If you are going on a short hop turbo props will be more efficient overall. This chart provides a nice outline of the difference in efficiency.

As for large piston pounders I am not sure of the efficiency but I would think the cost of keeping one running is high simply based on their age (no one is really making big piston planes anymore as far as i know). History channel has a nice show "Ice Pilots NWT" about a freight/passenger airline that still runs DC-3's and the general issues they have with them many of which is related to finding parts.

That being said not all airlines had the money to jump right into jets when they came out. Lots of turbo-props are still flown simply because there is no reason to replace them.

$\endgroup$
  • 1
    $\begingroup$ Also, jets typically require longer runways, prop airplanes generally need much less space, so are used for regional flights. $\endgroup$ – GdD Mar 24 '15 at 13:56
  • 1
    $\begingroup$ I don't know why you brought up piston engines, not all props are piston engines. Turboprops are turbines, just like jet engines. $\endgroup$ – MSalters Mar 24 '15 at 20:04
  • 2
    $\begingroup$ I also talk about turbo props and the comparison I posted via the link is mainly about turbo props. $\endgroup$ – Dave Mar 25 '15 at 0:17
  • $\begingroup$ I'm quite surprised that DC-3 users are having trouble finding parts, given that there are still several thousand flightworthy examples which could be cannibalised for parts if necessary... $\endgroup$ – Sean Mar 1 at 4:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.