Turboprops in RVSM Altitudes


#1

We have a non RVSM King Air B200. Looking at the various STC options for RVSM upgrades the same question keeps popping up: even if we upgrade to RVSM capability, will ATC clear us to those altitudes, given that we will be so much slower than the other jet traffic found there. To the owners / operators of such equipped aircraft such as a Piaggio, Pilatus or newer model King Airs I ask you this: does ATC allow you to routinely fly a route filed to those higher altitudes?


#2

Sure they will. You may occasionally have issues with ATC if you’re flying certain routes, doing Mach .48 down the Atlantic Route at FL350 comes to mind, but for the most part you shouldn’t see too much difficulty. I would imagine it’s more of an issue for a Kingair or PC-12 than it would be for a Piaggio, which can blend in with the slower jets at those altitudes.

The real question becomes whether or not you’ll actually use the capability. On the one hand, by not having RVSM on the Kingair, you sacrifice 20% of the aircraft’s usable altitude, which you might really want for weather avoidance, economy, range, etc… But, if most of your flights are 200-400nm, it might not affect your operations at all.

Also, keep in mind the resale value of an aircraft without RVSM will be less.


#3

Thanks for the reply. Most of our iteneraries in the B200 average around 800nm, so the extra altitude would be for fuel burn purposes and weather avoidance. Cost is an issue since this aircraft is used only under Part 91 and does not generate revenue. Also, since it is personal use, the flying hours available to recoup fuel burn cost savings are lower. So you’re right in saying that it should be considered. We’ve done several detailed analyses to determine payback and/or cost vs convenience of having access to those other altitudes. Generally, for the way we fly the plane, is comes out that if the package is somewhere south of $100k that it might be doable. So that immediately excludes a G1000 or a Proline retrofit. There are some other STCs that don’t include a wholesale panel refit that are cheaper, which would be what we are interested in.


#4

Check for the STAR STC, it was relatively inexpensive for a C560, but the 24 month inspection can be a little costly. There is another inexpensiver one I will look up tomorrow.


#5

For $100,000 I doubt you would ever recover the costs. That is looking at it from the accountants point of view. The question to ask yourself is how ofter are you at FL 280 wishing you could go to 320, other than to say you’ve done it!

John in Saudi


#6

I have to agree with John on this one. Unless you routinely find yourself wishing you could climb above FL280 for weather or if you’re carrying huge pax loads and need the altitude for max range, it’s probably not going to be cost effective. Sounds like you just need to talk the boss into a new airplane!


#7

Generally speaking, here’s how it works out mathematically as far as we can figure. We fly about 100 hours per year. Going up to the higher altitudes, we estimate, can save us around 10 gallons per hour in fuel burn. Jet A is averaging us around $5 per gallon. It’s in the $4 range at our home base but a lot of the destinations we fly to are in the upper $5 range so it averages out. So for a year’s savings you get:

100 * 10 * 5= $5000

We plan to fly the airplane for at least the next ten years. Over those ten years the price of fuel will most certainly go up, due both to currency inflation and the natural commodity increases prevalent in refined petroleum products seen recently. If current trends hold I think putting a 5% to 6% rate of increase is probably not outside of the realm of possibility. That includes the normal 4% rate of inflation. So one would need to compute compound inflation over that period which would be represented by:

sum(50001.05^x) where x=0 to 10
or
sum(5000
1.06^x) where x=0 to 10
The answer comes out to be between $71,000 and $75,000 to get even on payback.

The other $25,000-$30,000 is what we would be willing to pay for the convenience of being able to get above weather / turbulence / better winds.

I hope that makes more sense.


#8

Plus a bit better resale value.


#9

If you want to do it, you should do it. That said, if you’re trying to justify it financially, you need to consider the cost of the money that you have to spend on day 1. The value of $100,000 over 10 years is likely around $50,000.

$150k over 10 years (including the modification) would be to save $71-75k.


#10

Just a little off of the subject…a CJ2 or Premier would be better suited to an 800nm mission. You’d get the altitude performance you’re looking for, your block times would be less, Greater comfort as TP noise fatigue goes away, and best of all…the DOC’s are right there with a B200. The market is ripe for a good deal getting into either of those models too, and at a 10 year investment…


#11

That’s very true; if you look at the historical performance of the S&P500 with an average of 10% annual return investing that $100,000 will become $260,000 using a simple compounded interest formula. But if we were solely focused on the time value of money we would all be flying coach or driving to our destinations in Geo Prisms. So at some point, you’re right, one needs to “go for it”. With that said, though, I don’t think it needs to be totally black and white. Let’s say, for example, that you weren’t totally zoned in on the accumulation of wealth and you had a certain budget set aside for incidental expenditures. The question is how to best allocate that. In this case, RVSM might make sense, depending on a number of factors, some of which we are discussing here.


#12

10% would become $235k. I did 5% which becomes $155k.


#13

Seems like you’ve really crunched the numbers on this! If I were you, I’d contact HBC at Fulton County/Atlanta, Stevens in Greensville, or Elliot. They’d have lots of answers for you regarding options.

But then again, that whole CJ2 idea has an awful lot of merit…


#14

Maybe I did the math wrong. I used A=P(1+r/n)^(y*n)

P = principal
r = interest rate
n = compounding periods per annum
y = number of years


#15

Don’t get me wrong; that would be fantastic but even the oldest CJ2s would be over a $1M more than what our King Air would sell for. I’d love to be cruising around in a CJ2 or even better, a Premier.


#16

Believe me, I know how you feel. It’s always that pesky extra million… But we can always dream, right?


#17

The PC12 is only certified to FL300 anyway, so for that aircraft I’m not sure the extra 2000ft is worth the cost. That said, I never had any problems with ATC keeping us from reaching FL290 or FL300 in the PC12 when we chose to file for those altitudes.
In the P180 we never have any issues with ATC allowing us up to RVSM altitudes, and we’re in RVSM on almost every leg, at least those legs longer than about 250nm. If anything we get shortcuts off route if we get in the way!


#18

Your 200 won’t be able to climb up to RVSM altitudes unless the temps are ISA or less or if the airplane is light. I have 1500 hours in a 350 that is RVSM approved and I only use it in the winter and then only to go to 310. Probably less than 10 legs each year. I did FL350 once just to try it and it worked ok but I was 2500lbs below max wt and it was ISA-5C.


#19

You must live in the tropics, cause I can’t get above FL430 in the Lear in the winter till I get south of the tropic of Cancer.
Last month going into Connecticut I was at FL410 and had a RAT of -13.


#20

Your airplane must be a PIG! I’ve routinely used FL350 in both the 200 and the 350 with no problems whatsoever. The only issue is the cabin altitude, but we only did it with no pax onboard. The mistake most people make is to just go charging up at a ridiculous airspeed or climb rate instead of managing their energy carefully.