Cessna 337 push-pull

[PicMas]

I am looking into a possible project this coming summer. From my (somewhat limited) research done so far, it seems that the C337 will fit the mission profile best.

I am interested to hear about European based Skymasters and associated owners/operators that could be interested in a shortterm rental, 5-7 days and 25-35hours.

What should I expect to pay hourly for this type of aircraft - wet/dry?

PMs welcome

[proceeding outbound]

Having operated C337's many years ago I found the biggest problem when carrying passengers is there is nowhere to put bags, not even little ones. You can get a belly cargo pod!

We also had numerous reliability problems. Looking back it seemed like a good idea at the time but the C337 doesn't stand out as one of my favourite types I have flown.

[xsbank]

SkyMaggot? Suck-me Blow-you? Have to start the rear engine first or you might forget it. A good idea not really developed, IMHO

[proceeding outbound]

But don't wait to long to start the front one or the rear one will overheat.

On a serious note though, during the take-off roll it is a good idea to advance the rear engines throttle first so you know it is responding properly. Also, if you have obstacles to clear immediately after take-off you may want to consider delaying gear retraction as those gear doors create a massive amount of drag during the retraction cycle.

[John Miller]

Picmas - If you can find one available for a short term contract, I would guestimate around £350.00 per hour wet.

Quite a bit of time on the 337 - very few problems and very underrated. Loved it.

[Turban]

Really cool looking plane I always wanted to fly one of those !

Too bad they're on the way to extinction :(

Cheers

[AdamFrisch]

A very misunderstood airplane and one that I have researched extensively.

It sold decently, but never set the books at Cessna on fire for multiple reasons. Lack of baggage compartment was one of them. Noisy cabin was another. It's certainly a capable aircraft and you'd be hard pressed to find a twin that gives more bang for the buck. A pressurized turbo with full de-ice can be had for what a spinner on a Twin Bonanza would cost. And despite the statistics not supporting it (due to it being an entry level twin, mainly) it is safer in the case of an engine failure, especially during take-off. It was also accused of being slow, but this is not true. They regularly do 160-170kts and if you get the pressurized one up high, she'll do 200kts.

These are some of the things you need to know if you plan to purchase a 337.

1. The gear retraction is very draggy due to the big gear doors being flung into the slipstream, so most owners get the gear door removal STC. Makes the whole system easier to maintain as well.

2. Get the long range 148 gal tanks. They were standard from the mid-70's models, but an option on the earlier.

3. The rear engine needs a lot of cool air, so the cowl flaps get a workout. The electric cowl flap motor is a notorious point of failure and Cessna charges $2000 for them. So many get rid of it and install a manual lever system instead.

4. There's a recurring main wing spar AD inspection if it's flown more than 5000hrs (10000 for the pressurized model) every 500 hrs. It's not very expensive to do, but something one should know about.

5. This is the biggie: There's a proposal to do a very involved one time wing inspection AD that would cost much more than many of the planes are worth. It's a non-issue for private owners on the N-reg as it only pertains to commercially operated C337's. However, the nervous Europeans don't make that distinction and would most certainly impose this AD even for private owners, which would most certainly kill off most 337's flying on European registers. This is still a proposal, but it will most likely happen. Funnily enough it emanates from Cessna themselves as they don't want to keep supporting 30-40 year old airframes and want people to buy new. And the C337 got in the crosshairs first. But expect it to happen with 172's and 152's as well further down the line. It's an easy way of selling some new planes.

If you buy, know that there are tons of modifications for the 337s. You can get dual tip tanks added, taking capacity well over 200 gal. And if you really want intercontinental range, you can add under wing tank pods and get up to 400 gal if you wish! There's the aforementioned belly cargo pod that only slows it down a couple of knots (most people just remove the last 2 seats and stick the baggage there). One piece windscreen mod. 3-blade MT prop mods, STOL kit etc, etc.

As I said, bang for the buck it's hard to beat. I even happen to think it looks great. It can get into any field you can get a 172 into - grass, gravel, whatever. Most other twins are far to delicate to plop down on a rough field. Visibility is great etc, etc.

Get one;)

[jarvis123]

At the risk of drifting the thread, anyone remember the 337 op by Cumbria Police in the 1990s?

[SNS3Guppy]

I disagree regarding baggage space in the 337; it's got a problem no more than any other similar light twin. I've operated them with standard baggage, and in special configuration with personnel seats where the baggage compartment used to be.

Many operators remove the gear doors; it's an STC mod, and eliminates the hassle of the gear doors. Otherwise, the gear system is typical Cessna, and one reticent of the single Cessnas (EG, C210, 172RG, 177RG, etc). Easy to manage, easy to handle if the system has a problem, etc...but one must know the system.

The 337's biggest weak link is the fuel system, which surprisingly has lead to more crashes, engine failures, and fatalities than any other aspect of operating the 337. It shouldn't be that way (obviously). It's really not that complicated. As others have noted, long range tanks vs. standard tanks, or STC-mod tip tanks make differences in the way the system is operated. I've flown the various models, and my favorite was a dual, long-range tank system using tip tanks. I was able to get 12 hours duration out of the airplane.

Reliability was never an issue in the airplane, but like many light, piston twins, don't expect stellar performance with an engine out. The solitary engine failure I experienced in a skymaster was due to maintenance action; a newly installed engine lost all oil due to failure to properly secure the drain plug. About 30 minutes into the flight, oil pressure and temperature dropped to zero and the rear engine had to be feathered. A return to land at the departure airport was uneventful. On the ground, the cowl and horizontal stab were covered in oil, and removal of the cowl quickly revealed the problem. Otherwise, I found the skymaster to be extremely reliable under extremely adverse conditions.

Cessna just introduced a host of service bulletins regarding the skymaster for inspections, some of which have become, are becoming, or will become AD's. One in particular is over great interest regarding a wing failure, directly tied to the use of tip tank extensions.

The skymaster is far from extinct, and is in hard, daily use in some of the most challenging spots on the globe, presently.

As others noted, lead takeoff with the rear engine first, and monitor the power instrumentation during the takeoff.

I haven't had problems with overheating the rear engine, even in extremely hot desert conditions. Slow flight with heavy loads wasn't a problem, either, for extended periods, and the rear engine has enough cooling capability. Various mods are available to help increase cooling, however, and are in use in some 337's being operated in hot, adverse conditions.

Much of my flying in the skymasters has been done in the turbocharged models. Don't waste your time with the pressurized models, but a standard turbocharged airplane is the best. If you're not going very high or very hot, then a normally aspirated airplane is fine.

Forget de-ice. The airplanes are available with various de-ice, but it's not a design that should be flown in the ice, and wasn't approved for known ice. Don't try to use it beyond what it is: a basic, light piston twin. Treat it accordingly.

[Gulfstreamaviator]

flew 250 hours on one many years ago.

great fun shutting the front engine down in the cruise.....kept the pax awake / alert too...

always advance the rear engine first, to ensure it is asctually operating, cos if you raise gear, aircraft will sink first, and perhaps the mod to the gear doors will be FOC.

great short field performance too.

glf

[JammedStab]

The 337's biggest weak link is the fuel system, which surprisingly has lead to more crashes, engine failures, and fatalities than any other aspect of operating the 337. It shouldn't be that way (obviously). It's really not that complicated. As others have noted, long range tanks vs. standard tanks, or STC-mod tip tanks make differences in the way the system is operated. I've flown the various models, and my favorite was a dual, long-range tank system using tip tanks. I was able to get 12 hours duration out of the airplane.

I haven't had problems with overheating the rear engine, even in extremely hot desert conditions. Slow flight with heavy loads wasn't a problem, either, for extended periods, and the rear engine has enough cooling capability. Various mods are available to help increase cooling, however, and are in use in some 337's being operated in hot, adverse conditions.



Flew the 337 normally aspirated a lot. A bit on a turbo which I remember having a service ceiling of 29000 feet.

It seems the fuel system could be extremely easy if you just had the long range tanks, 1 per wing. No switching required at all. But when you have two tanks per wing it is completely different. Here is an accident report and a description of the fuel system and operation in two links. It is very interesting and mandatory reading if you have this system. The crossfeeding operation can be very interesting.

Transportation Safety Board of Canada - AVIATION REPORTS - 2008 - A08C0124 (http://www.tsb.gc.ca/eng/rapports-reports/aviation/2008/a08c0124/a08c0124.asp)

Cessna 337 Skymaster Fuel Management (http://www.consultresearch.com/337fuel.htm)

Read a lot about hot running rear engines but only experienced it once. During an engine run. It was cold out so I foolishly didn't do an extended run into wind like we all learned to do as students so the temp came up but went down quickly once pointed into wind.

[SNS3Guppy]

The long range tanks are actually two tanks, plumbed as one, but some tanks utilize switching for inboard and outboard on each side. The tip extensions generally get pumped into the main tank, and don't require additional switching.

Like some other twins, the problem can come with an engine out, when fuel returned off the engine in use from fuel pump bypass isn't going to a tank where fuel can be reached. One can run the engine out of gas and still have inaccessible fuel remaining.

Most interesting of the incidents I saw was a pilot who departed on a night flight and ran out of fuel with an imbalance, because he hadn't used his checklist. He didn't check his fuel selectors before takeoff, and burned everything off on one wing with nothing touched on the other. In the end, he returned to blame the mechanics for not positioning the fuel valves as he desired them to be. Idiot.

[N707ZS]

There are quite a large number of 337s in Spain but most are used as fire spotters in the summer. Perhaps try the Spanish forum.

[skymasterO2A]

Hello!


Flew Navajo, Aztec, 336/337, mid 80s on a 135 operation, 336/337 were more productive, no problems.
Talk to O-2A/B pilots, A&P's civilian and military. They virtually had to be blown apart for them not to make it back, even with heavy and under rated claims during Vietnam War. Dives, pulls, recoil from weapons, battle damage. We did passengers and cargo in the Caribbean, hot, humid, all kinds of landing surface . Many still going today.
The AD, my opinion, marketing move, check the time tables and the fate of the Cessna 162 Skycatcher. I hope is not the beginning of the end for the corporation.
When I retire, I will buy a Skymaster.


Be Safe and don't challenge mother nature.

[JammedStab]

Always started the front engine first. Why start the rear one first. Just because you might forget it. In over 500 starts, I never did.

With the long cable to the rear engine, there was a lot less starter torque in my experience.

[lifeafteraviation]

Loved that plane...flew three of them all pressurized. I recall problems with the magnetos at altitude...needed pressurized magnetos or something....been such a long time.

Can't remember the engines? Was it a Lycoming 520?

I used to haul spare engines in C206 and C207 a lot. They had no trouble doing it...I often thought it was like flying the 337 with one shut down and we joked about being able to log ME time.

[Sop_Monkey]

Hmmm 337

Reminds me of a time years ago and I was driving home from a night out at Hicksville. About 11 pm and this 337 landed, went over to the aircraft but couldn't find the pilot anywhere. I did make inquires but to no avail. I did however find out that the owner/pilot was a nasty piece of work. As for the aircraft, well it was in good shape on the exterior but inside? It was horrible. The aircraft was painted black

[AdamFrisch]

Ha.

Night Flier.