Hi

has anyone operated this aircraft and has some info for me.
like
normal cruise speeds?
actual fuel flows ?
known problems to look out for
or something that you might think is important to know about these machines

(sorry if this topic has been up before)

//Johan

Lots of info here:
https://www.jerrytemple.com/temples-tips.htm

It's been a while, I recall 185-190 KTAS cruise speeds.
40 gph (125 deg ROP).
You don't want to get into serious icing (actually, pretty much true with any plane).
Not difficult to learn proper operation, but the fuel system is somewhat complex.

Many years ago I was in the search for a good 340 as my first twin coming out of a T-210 that I owned for 14 years. I flew several times with a pilot that had two 340’s in a 135 charter op and got some time in the right seat to see how they flew. He said he flight plans for 180kts. Others on these pages said they get closer to 200. It handled a lot like my 210…very stable, bordering on ponderous. My uncle (who flew an Aerostar 601-P in Switzerland) told me that before I buy a 340, I needed to look at and fly an Aerostar as an alternative; at the time, I had never heard of them. I flew in one and was instantly sold. I owned two of them over about 10 years before moving on to my current MU-2.
I do feel the 340 is a good plane, but it seemed that for a similar fuel burn, purchase price and maintenance rate, you could get a plane that handles like a dream and is remarkably fast and efficient.
I never had to own and maintain a 340. In that vein, the Aerostars were both pretty demanding of my attention, learning, and time with a wrench. That was not the case with our T-210, but I’m sure any pressurized twin will ask a bit more of its owner than a 210.

I think Dr. Bienz and I may have the same icing story!

How does the aerostar cabin and cockpit room compare to the 340

AStar is great if it’s just you and 2 passengers and not long distance.

The 340 is much better for a family plane. Bigger cabin, passengers can change seats easily , MORE LUGGAGE SPACE and you can install a PORTA potty in the back.

I believe it’s quieter than the ASTAR. My RAM VII had a 205 KT cruise in the mid teens.
It was faster if you went higher. The fuel system is not a problem if your IQ is higher than room temperature.

I'm a little bit familiar, having owned one for going on 7 years now. I love it.

If you're serious about buying one, join the Twin Cessna Flyers group, and go to one of Tony Saxton's System Seminars, which he holds a few times a year. That's how I started before looking for a plane.

I have a RAM VII STC, and RAM publishes a chart for target fuel flows vs. altitude and OAT. I am generally running in cruise at 17 GPH per side, which is ROP at 69% power. For that setting I'll get 180 TAS down low and 205 TAS at FL230. I used to run LOP at around 15 GPH and a couple knots slower, but I haven't been able to get the engines to do that recently at peak EGT temperature I was happy with for the turbos. I do not have GAMI injectors, that may be part of the issue.

I climb at 28-29GPH per side, targeting 130 KIAS. Climb rates vary based on temperature and weight; I was getting 1200+ fpm to mid-altitudes this winter at lighter weight, but 700 fpm is more typical up in the flight levels.

As far as important things to look for, it's not too much different from other planes; normal engine concerns and corrosion are the expensive things to worry about. Continental 520s have been plagued with cam / lifter spalling issues over the last decade on all airframes; I've done two tear-downs for this on my plane to replace the camshaft (each side once). I'm beyond TBO on both sides now, and presently swapping out one of the engines. In 1200 hours of operation, I haven't had to replace any cylinders. Compressions have always been good.

There is an extensive exhaust AD, requiring visual inspections every 50 hours, a pressure test and tailpipe inspection annually, an inspection of the canted bulkhead at 500 hours, and a 2500 hour / 12 year send-out-the-whole-exhaust-for-inspection step. Before the AD back in 2000, there was an issue with fires caused by poorly maintained exhaust systems, and as far as I can tell those issues have been solved by the AD.

Twin Cessnas in general have a reputation for gear issues -- don't abuse it with side loads. Like many of the Beech products, the gear is driven by a single motor with linkages to each of the gear. If one of those linkages break, you're stuck. The manual extension bypasses the motor but not the linkages. Re-checking the tensions on all the gear linkages is recommended annually.

Like many 6 seat planes, I don't find operation with that many people is practical. I've probably only filled the seats a handful of times. With the zero fuel weight limit, you better have 5 light weight friends that pack really efficiently. For two to four people, I can carry about as much as can fit in the minivan on the way to the airport. Lots of space in the nose or back of the plane. The wing lockers are a nice adder, but fairly shallow. I have all my utility stuff in the left locker (chocks, spares, cowl plugs, etc.), with the right side open for baggage and/or the sidewinder tug. You will find useful loads in the 1700-2000 lb range.

The factory air conditioning was a hydraulic system that sat behind the right engine. A bonus is to have the Keith electric system, which goes in the nose, on the left side of the nose gear. I don't think retrofitting the Keith system is possible any more.

Basic fuel load is 163 gallons, tips (mains) and wings (aux). An option is a nacelle tank, 20G on one or both sides. The factory AC takes the place of the right nacelle tank. My aircraft has 203G capacity, but it is rare that I fill all those tanks. With 3 or 4 people on board plus baggage, I don't have the MGW room for that. A rare few aircraft have even more capacity for fuel, I don't know how they stay legal on take-off. Assuming a climb to the flight levels, I figure the first 100G is 2:40 of flying, then 3:00 remain. So 5:40 of flying on 203 gallons to empty. I aim to keep legs less than four hours, and have maybe gone to 4:30 or so.

The plane has too many damn fuel pumps. Mine has 11, and I think I've replaced 6 or 7 of them so far.

Some STCs available include four bladed props, strakes, speed brakes. I don't have any of those. Both the GFC 600 and the STEC 3100 are approved on the 340. I have the STEC 55X.

Among our airplanes is a 1981 C340A. Our guys just love it. We get C421C performance for $100,000 less investment and $100 per hour lower operating cost. We routinely fly it at FL250 and see 215 Kts. Below 10,000 airspeed is about 180 Kts. Fuel flow is 36 GPH. With the 200 Gal fuel system, range with reserve is about 800 nm. Aerodynamics are great and control forces are light. The airplane can also be operated under Basic Med with some considerations. CG management is not an issue.

There are a few problems. Useful load is low, about 1850 Lbs. Must have a RAM-something Mod. Fuel system is a problem with six tanks and ten pumps. Not all the fuel is usable in either engine. NTSB accident reports show a number of accidents due to fuel mismanagement. Cabin is small but not really cramped. The exhaust system AD is an issue.

Insurance can be a problem for someone with less than 750TT, 100 ME, and no Instrument rating. Transition markets are available, but may be expensive.

Sabris Corporation, Wichita. David Dewhirst ddewhirst@onemain.com 316-655-2821

One more thing... picking a new plane, I'd value the RAM VII conversion (with a new intercooler and scoop), or a plane with the AA intercooler over others. I think the larger intercoolers are key for efficient operation and cool running engines. Because the intake temperature is lower, you run further from detonation and can be leaner. With RAM VII, my plane is rated for full power all the way to 23,500 feet.

I got mine with 450TT and 25ME, but times were different 7 years ago. I pay about $5K a year with annual recurrent training. I went looking for an insurance quote before looking for airplanes. If they said I needed 100 hours of dual or something, that would have been a non-starter.

I previously owned an Aerostar 601P/SS700, currently own a C-414 and have been involved in the maintenance in three C-340's, 414, and 421C. I have a few hours flying another 340. I have around 2000 hours in most piston Twin Cessna's and about 250-300 in the Aerostar.

Most of the details have been hit in the above posts. I loved the Aerostar. It's a gret airplane, fast, and extremely well supported by Aerostar. My general impression is the cabin is very similar in length to the 340, slightly shorter and similar width. The airplane was a little awkward to load until you figured it out, then it worked very well.

I bought the Aerostar because it fell in my lap at an embarrassingly low price that I couldn't resist. 24 hours before I owned it, I knew almost nothing about Aerostars. Over time, I learned what an incredible airplane it was.

The only reason I keep that class of airplane is for charity flights. I'm on the board of one of the charities that reimburse for fuel, so fuel cost are relatively insignificant to me. 75% of the flight time each year is charity flying.

The only reason I put the airplane up for sale was I wanted a larger, more comfortable cabin for the recipients. I was originally looking at 340's, but needed more weight capability. My second choice was a 421C, but I had a customer wanting to sell his 414 and we worked out a great deal.

Dollars wise, both airplanes are about equal per year. Each has its pluses and minus'. The 340 cabin is slightly more comfortable for passengers, especially in the rear seats due to headroom and general room in the middle row. I had a sixth seat for the Aerostar, but only used it once. It was useless for anything other than a group of kids.

In the Aerostar I could make mid-Michigan to central Florida non-stop most days. The 340/414 has to be idea conditions with a slight tailwind do do the same flights. With the aux tank and using the fueling trick, you can get 230+ gallons of fuel on board the Aerostar verses 203 max in the tip-tanked Twin Cessna's. That, with the extra speed gives you a few more miles of range.

Personally, I loved the way the Aerostar flew. Even with a headwind the ground speeds usually started with a 2. The Twin Cessna is a more comfortable airplane. There are (good and bad) mechanics all over the place that know the airframes. The Aerostar has some good shops around the country, and a few big named shops that have good down hill recently. I flew enough Twin Cessna's that I wear them like a glove even with time between flights. I was comfortable in the Aerostar, but it never felt like a glove to me.

If looking for a Twin Cessna, as Adam said join the Twin Cessna Flyer group. For the Aerostar, the (relatively expensive) Aerostar Owners Association is a great group. Both produce great magazines.

Each have their own maintenance issues. I fought the wastegate rigging on the Aerostar during my entire ownership and never got it right. I finally took it to a great shop for the prebuy and he still didn't get it perfect. The Aerostars are generally lower times airplanes. If you want to shame a King Air 90 pilot, pass them with an Aerostar.

The Twin Cessna's have a few issues also. Engine beams, deicing boot valve issues, gear rigging and landing gear side braces to name a few.

Either one is going to require (likely) annual formal training.

Jason, what charity reimburses for fuel?

Doug ‘s advice above is solid. I had a 1981 Cessna 340, for about 4 years and just under 500 hours. I had additional fuel, allowing 203 gallons total. I flew that thing all over the eastern United States, Canada, and the Bahamas. I did a few long trips with six people. Although a bit crowded, it was workable. We had a porta potty in the back for the kiddos.

Keeping the engines tuned is the key to success in that airplane, as well as looking after the exhaust components. If you stay on top of it, it is very easy, but it is an airplane that requires some level of owner involvement. I was even able to run mine lean of peak, but ultimately stopped doing it because it was very slightly less smooth. I would see just under 200 kn at 38 gallons per hour, 18 to 20,000 feet. It is an awesome traveling machine, and I flew it in all kinds of weather. Once I had up to an inch of ice on the airplane, while climbing through, and it’s still performed normally. Although not recommended, it didn’t seem to struggle with ice.

another key to success, is make sure that it is maintained at a shop familiar with Twin Cessnas. Every mechanic will promise you that they are, but the truth is very few shops know the intricacies of those models.

I would have never sold it, but I had the opportunity to dry lease a single engine turbine with no capital outlay. It was a no-brainer. If I needed an airplane tomorrow, and I could buy my 340 back, I probably would.


more info here:
viewtopic.php?f=3&t=43207&hilit=340+cessna+340&view=unread#unread

Good luck!!!