Old Jet vs Turboprop

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Mr. Greenspun,
A bit of consulting on buying planes. I was thinking of getting a
Piper Malibu, pressurized. Say around 1995-1998 years. I want to carry
5 people, have a range of around 1,000 nm, for flying from Bangkok to
Chiangmai, or to hit the beach in Phuket.
And then I found another very interesting category of planes, old
business jets. I found one a 1979 Learjet 24F that can go a whopping
FL430 for around 600k USD. And a 1976 Lockheed Jetstar that has
something like 2,000 nm range, enough for a nice trip around the region.
Please forgive me, I'm a bit new a this. Thailand has a very small
private aviation community.
I know airlines still fly planes older than this around There must be
a reason why they are quite cheap, compared to other offerings. What
would be the maintainence cost like on one of these jets? Properly
maintained, are they safe to fly? For the older jets, I was thinking
of adding a storm scope, and TCAS I, that should help with the
situational awareness some.
For 600k USD, that's in the Cirrus range, but you get a jet that
flies higher.
Your take on this please, Mr. Greenspun.

Bangkok, Thailand

-- Somsak Supakit, September 30, 2008


Once you go from the Malibu to the ragged-out old Jetstar, why not keep going and pick up a Boeing 727? I think that you can get airworthy B727s for $250,000 and carry more than 100 friends in comfort.

Conklin and Decker, http://www.conklindd.com/, can supply operating cost estimates for all of these airplanes. Old jets are useful for people who want to say "I own a jet" and who don't fly very often and/or for some reason need to leave the jet parked for long periods of time in out-of-the-way places. If you fly 50 hours per year, I'm sure it is much cheaper to be a fractional owner of a modern plane. If you fly 100 hours per year it starts getting cheaper simply to own a modern plane outright (though many people who could own a plane choose to continue with fractional so that they don't have to hire pilots, manage the plane, etc.).

If I were to trade in my Cirrus on a Learjet or Jetstar, insurance would go from $3000 per year to $30,000. Because the Learjet cannot be flown legally by a single pilot, I would need to hire at least one full-time pilot and pay $10,000 per year for his or her recurrent training. I would need to pay $10,000 per year for my recurrent simulator training. I would be paying for hotels and meals for my crew whenever we traveled. The hangar expense would go from $600 per month to $2500. Fuel and maintenance cost per hour would go from $120 per hour to maybe $30000 per hour.

Anyway, once you've totaled it all up you could probably own an old Learjet for about $300,000 per year in fixed costs and another $300,000 in operating costs if you flew it 100 hours, i.e., about $6000 per hour. That's a little bit more expensive than NetJets would charge you for flying in a brand-new much larger business jet. And if the NetJets machine happened to suffer a mechanical problem, they would send you a new one with a fresh crew of two pilots within a few hours.

-- Philip Greenspun, September 30, 2008

Run some performance calculations before you decide. Is it absolutely necessary to get above FL400 to get a sensible fuel burn? What is your range if you are forced to stay in the mid 20s to 30s flight levels? Check RVSM in your area and for the plane. I'm guessing the Lear is not RVSM certified (the hull cost is way too low to reflect that). A lot of the older LJs are being cast aside here in the U.S. for two reasons: 1) the cost of the RVSM upgrade exceeds the return, and 2) Fuel burn in the old turbojets is stunningly high below about FL400.

Also, I can't remember if this was in the 24, the 25, or both, but one of the early 20 series had some pressurization problems. Taking it to max altitude would also require near max power to keep the cabin pressurized. That is, pulling the power back for descent would also initiate a cabin climb (and in some models) causing a cabin altitude warning.

Also, more conjecture because my memory is worn and tired, but I believe the F model 24 has the wing mod that allows the ref speed to be lowered. That is a good thing. The early model high ref planes required a great deal of skill to fly. If you're looking for something that can haul a good load of people, fly in the flight levels, and is relatively fast, consider the PC12 with the /47 gross weight increase. (I'm not sure, but I think the NGs come with the /47 mod.) I realize however, that may not fit the $600K budget well.

-- Jason Hackney, September 30, 2008

Thank you for you responses. A "jet" the price of a single piston, sort of blinded me to the facts. In my country, there is no equivalent of Net jets. The private aviation community is extremely small. But the interesting thing is that, a luxurious sports car in my country, has a 700% import tax. While a plane has 0% import tax, plus there are more tax breaks for my company. So, a Ferrari would be around 1 million USD plus here, I'd rather get a nice plane. Now that I have some perspective, perhaps a TBM 850, or a Citation Mustang would fit my requirements more. What's the maintainence of a PT6 engine like? I know it's quite an ancient design, compared to the newer jet engines. Somsak Bangkok

-- Somsak Supakit, October 1, 2008


Experienced pilots and owners looking for airplanes in the category you are considering usually hire consulting help. You usually get what you pay for. Since your aviation community is very small, there will likely be constraints based on what you can get maintained easily in your area. I would suggest you try to meet with existing owners in your area and see what they will tell you. Beware the ones that quickly want to sell you their problems though.

Your situation is just one reason the mighty King Air holds it's value so well. It is not cheap to operate compared with the more modern singles, but there are mechanics and pilots everywhere. Also, you can often charter one out when you are not using it.

Lastly, you might want to make sure that Avgas is readily available for you. This may push you into the turbine as well.

-- Eric Warren, October 2, 2008

Buy a used King Air 90. Reliable and Beech is still making them and their parts.

-- Max Rosenberg, May 26, 2009