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Say you wanted to outfit an ATR 42-600 for executive transportation like a smaller version of an Airbus ACJ 220. For example, 2 living areas of 4 rows, 1 sleeping area of 3 rows (a double below and a single above on both sides), and increase galley and lavatory by 1 row.

In commercial layout the maxpax range is 720nm. Could the the above executive config get close to 2000nm range? Looking at the King Air 360er range of 2500nm for such a small plane I'm thinking it could be possible. Less weight. Maybe convert some baggage area to fuel tanks. Possible?

Also, I know there is at least one VIP variant out there but it only converts about half of the cabin and leaves the other with economy seating. I imagine that would be heavier than the above.

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    $\begingroup$ Worth noting: executive configuration is not light... Plus th ATR is not one of the quietest airplanes, so something would need to be done to that too. And it's slow, so... $\endgroup$
    – Jpe61
    Jun 29 at 13:27
  • $\begingroup$ @Jpe61Not true on the noise. Modern turboprop cabins are just as quite as jets, both private and commercial. $\endgroup$
    – Edmund
    Jun 29 at 13:48
  • $\begingroup$ Why the ATR? Why not start with something that’s longer range to begin with? $\endgroup$ Jun 29 at 15:11
  • $\begingroup$ @MichaelHall Cost and size. An ATR 42-600 is less than 10mil. So if it could be converted and get the 2000nm range for a couple of mil then you basically have a jumbo King Air for less than twice the cost. $\endgroup$
    – Edmund
    Jun 29 at 16:09
  • $\begingroup$ @Edmund the ATR's I've travelled in absolutely cannot compete with , say, 737MAX, or don't come even close to A350... Noise, vibrations, no chance. $\endgroup$
    – Jpe61
    Jun 29 at 19:06

2 Answers 2

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No, it wouldn't be possible as the airplane cannot carry that much weight. The ATR 42-600 has a maximum take-off weight of 18,600kg, and an empty weight of 11,550kg, so its maximum load is about 7050kg. It's maximum fuel capacity is 4500kg which gives a range of 720nm, which equates to 6.25nm per kg of fuel. If we use that figure for a range of 2000nm the weight of the fuel is 12,500kg, which is 5000kg over the maximum weight. That 12,500 weight is an over-simplification as airplanes burn much more fuel to get up to altitude than in cruise, however it's close enough to illustrate the problem.

Typically extended range versions of an airplane add somewhere between 25-50% to the range, for example the King Air 360er you mention has 38% more range than a regular 360. You are proposing a 180% increase in range, which will almost always be outside the range of possibility.

One thing you also have to consider is it's not just about weight, you have to consider where that weight would go. Fuel weight has to be spread around center of balance, if you just add a bunch of fuel tanks at the back your airplane will be too tail heavy to fly. There's also the weight of the tanks, fuel lines and pumps you'd need to deliver the fuel to the engines.

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  • $\begingroup$ The King Air 360ER isn't a good example, since the ER variant has a higher MTOW (16 500 lbs) compared to the regular 360 (15 000 lbs). If you increase the MTOW of the ATR, you could also get more range, but probably not that much... $\endgroup$
    – Bianfable
    Jun 29 at 12:45
  • $\begingroup$ So back of the envelope the best you think can be done by reducing the empty weight with an executive fit out, reducing passengers to 6 to 10 (instead of 42), and using empty weight savings as fuel is a 40% increase to 1000nm. Still curious how the increased percentage of takeoff weight as fuel would extend the range as (like you noted) it is not a linear relationship. $\endgroup$
    – Edmund
    Jun 29 at 12:58
  • $\begingroup$ I'm not saying it's a 40% increase in range @Edmund, that's the increase from the example you gave. A typical seat weights 15kg, getting rid of 30 seats only saves you 450kg, that's a 10% increase in range using the figures in my answer. $\endgroup$
    – GdD
    Jun 29 at 13:00
  • $\begingroup$ Yes, but you are forgetting the human weight. 42 humans at 80kg is 3360kg. Plus thier baggage say at 10kg each is another 420kg. So all up seats 450kg + humans 3360kg + baggage 420kg == 4230kg. Even if the executive furniture comes in at half the weight of the commercial seats we are still taking 4000kg of additional fuel on a lighter net fuel weight. $\endgroup$
    – Edmund
    Jun 29 at 13:34
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    $\begingroup$ The empty weight of the airplane is without passengers and cargo @Edmund. The difference between the empty weight and MTOW is 7050kg. If you gave all that over to fuel, assuming that the weight loss from removing seats and the weight gain of the extra fuel tanks and piping equal out, then the increase in fuel is 55%, and that's with no seats, cargo or passengers. I've clearly articulated it in the answer and comments, take it or leave it, that's all I have to say. $\endgroup$
    – GdD
    Jun 30 at 12:28
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You could get a little closer with an ATR 42-600F conversion.

What you must do is figure how much the customized interior with passengers and luggage will weigh, the rest is fuel.

More weight could be borne with a larger wing with some sacrifice of cruise speed performance. This would be off-set by the ability to carry much more fuel and ...

More power will give the ability to fly higher, essential to maximizing range$^1$ and improving TAS.

The ATR 42-600 is designed and highly specialized for the short-medium range market niche, whereas a long range aircraft, such as a Gulfstream G700 is needed here.

A lot would depend on how much customizing they would be willing to do.

$^1$ larger wing helps here too, allowing lower IAS for a given TAS, or Mach number.

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  • $\begingroup$ Good idea to start bare bones and build up. It's all ready at 900nm fully laden. Wonder what it does empty. Could see if Comlux would do the outfitting. $\endgroup$
    – Edmund
    Jun 29 at 13:41
  • $\begingroup$ I have fond memories of the Handley Page HP 42 Nothing in engineering is too ugly if it works well. $\endgroup$ Jun 29 at 13:44
  • $\begingroup$ Good suggestion, but maybe better as a comment? $\endgroup$ Jun 29 at 15:10
  • $\begingroup$ The 1940s solution: two more engines, better supercharger, oxygen masks $\endgroup$ Jun 30 at 7:24

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