[hharney]

The pressurization system on the P model is probably the simplest systems in the aircraft. Other than leaks in the pressure vessel, there is really nothing else that is a concern. It works well but is only a 10,000 ft cabin at 20,000 ft. When comparing pressurized planes that's not much differential. There is a purpose for the P model so don't make it what it isn't. The added weight to the P model is substantial so why would you buy one and then not have a use for the very purpose of the model? I could never understand when folks wanted to make the 337 a fixed gear airplane. But I am sure someone could come up with a reasonable reason.

What's the mission, as you have described in other threads, buy the model that fits the mission. One thing to consider is the environmental system (cabin heat) for the Turbo and the P model is a Janitrol gas heater. With the normal aspirated models the heat is directly off the mufflers. The Janitrol can be a finicky item and expensive. Maybe you are familiar with them, have you had a gas heated aircraft? I have always thought simple is better but in some cases the mission requires the gas heater.

With your mission being 1-3 hours twice a month in the North East it may be that a normal aspirated Skymaster will do a really good job for you. These flights may be easily accomplished with the standard NA airplane. If weather dictates ICE there is NO Skymaster model that can launch into Known Ice. So if weather keeps you from going and you have to be there then you are looking at the wrong airplane. If you can say leave a day earlier or stay a day later for the weather to pass then the Skymaster will do the job. Even the P model at Flt Lvl 160 or 180 won't get you over most summer weather. It may provide a better ride but you will still be deviating for build ups. You didn't mention how many seats are required. If most flights are 1 -2 people then a heavy plane with work but if you need 4 seats for adults then the P model can be restrictive. Fuel loads for 1-3 hours are pretty simple in any of the models. The occasional long trip every year will require a fuel stop but once a year is reasonable. If you can afford the P model price and upkeep then it's a great tool for what it does but there are a lot of Skymasters sitting because someone bought them and can't keep them in the air. Fuel cost and maintenance grounds them because the low purchase price attracts a buyer that can't maintain the airplane. Therefore it makes for a difficult quest to find a good, well maintained Skymaster aircraft. The good ones just aren't listed for sale because the market won't justify selling the aircraft for the money they are worth. Owners keep them because they love them and can't really justify something else.

Bottom line, find a 337 that has been taken care of, that fits your mission or be prepared to spend some money to bring the airplane up to standards. The best Skymaster to buy won't be listed on all the usual sites. It is being flown regularly, maintained and you will have to sweet talk the owner in selling the plane.