I have owned both a C310R and a B55 President II. Both are terrific airplanes. So much nonsense about either being hard to fly, easy to fly, good/bad instrument platform, etc. They are airplanes.

But, if you want performance, the B55 PII is truly my favorite. It's the only plane I've flown that you could say it has almost enough power. The single engine service ceiling is way above 10000', and single engine work is a non-event.

But, if you want to haul a lot of stuff and people around, the extra room of a 310R is excellent.

I've flown both from Alaska to Florida, based in SoCal most of the time. I owned the 310 for about 5 years, sold it to get a 421B, and enjoyed that a lot. For "economy" I got the Baron and had that for 17 years, sold it just as Covid was taking off, and hung up my spurs. I must have liked it.

The 310 was a slightly unusual combination of normal aspiration and FIKI. I had some ice on it intentionally a few times, but it never affected dispatch. The extra power of the Baron, with alcohol props, was pretty effective too.

So, for a couple, and occasionally two couples, it would be the Baron PII. For a couple with more than two kids, the 310.

I have a smaill amount of 310/320 time and thousands of hours in the A55/B55 Barons (stock IO-470L's, Colemill IO-520E's, and my current power - the Cygnet STC which basically is an IO-520E 285 HP conversion). Curt's analysis is the most succinct and accurate I have read without going into crazy - but perhaps entertaining - back and forth discussion. They are both great light twins.

Thanks all for the wealth of info. I flew my friend to Mt. Pleasant, SC for a meeting yesterday and there was a spotless 310L on the ramp. He was very impressed with it and I believe is beginning to see why I’m steering him in that direction.

He’s flown in plenty of Barons with me and with other folks, so it’s a known quantity. Once this Lance sells, the next step might be to find someone in the mid-Atlantic region to give him a ride in a Q/R so he can get a feel for what they can do.

Corrosion is a big problem in 310's, they had virtually no internal corrosion protection when they were built. The nose near is notoriously weak, and the main gear can't take much of a side load without risk of collapse if it doesn't have the heavy side braces. Expect to spend $$$$ each year on a thorough gear inspection and re-rigging. Engines: case cracks are common on pre-1970 engines. A pre-buy should pay close attention to the cases, along with careful evaluation of the cylinders for exhaust valve problems. Check the starter adapter for signs of slipping by cranking for a minute or two with mags off and fuel off. While the cabin is wider than a Baron, it's no taller. The front seats are great, the middle seats are OK, but the back two seats are pretty much like sitting on the floor. Good for small children only.

I see you're really focused on the speed compared to others. When hauling non-pilots. comfort is more important than speed. And the difference between a 165 knot and a 190 knot twin is all of a half hour on a 700 nm trip. Which is about as far as you can go with any of them stuffed full of people and bags. The guy sitting on the floor, with his knees in his face, in the back row of a 310 for 3.7 hours, would be much happier sitting upright in a real seat in the back row of an Aztec for 20 more minutes.

Not in a strong headwind. Speed is a comfort thing, too, and half an hour is a pretty significant difference which will grow in a headwind.


Starting in 1972 and later model years, the 310 cabin height was increased behind the front seats and they got a rear window.

Mike C.

Haven't had any corrosion issues with the L or R, same as any other aircraft in being prone. Actually, better than the beech products that have magnesium surfaces.

I'd sit in the back of my R just to see what it felt like, not cramped at all at 6'2.

Landing gear isn't that big of a deal. I didn't rig my R by the video annually, just a gear swing. 5 years later the new owner just did it by the book and said it needed next to no adjustment.

Glenn what is your basis for these claims?

Nose gear failures, in most cases are due to jamming on retract, either from an under inflated strut or some other interference, causing the linkage to fail at the idler arm under the floor. Once this linkage is compromised the aircraft will be landing on its nose as there is no way to extend it to its over-center locked position.

"heavy side braces"? What do you mean by that? Are referring to Cessna Service Kit SK414-8E? This kit, like the wing root repair kit for a Baron, is a repair for cracks in the rib and wing skin, due to repeated flex from high speed taxi turns. Cracks in the rib, unless so severe that upper pivot is significantly displaced, are not going to allow the main gear to collapse. Here is a photo of the upper pivot bracket. It bolts onto the back-to-back angle doublers at the top and bottom of the wing rib. Quite a few rivets where the wing skin attached to the rib would need to sheer for this bracket to be displaced.

For some reason having this repair is considered an upgrade. Now Cessna and RAM began installing these parts on the later models because of the increased gross weight. The kit itself is still available BUT the extra parts required to install it on the older models are scarce and/or prohibitively expensive.

Older 310's for the most part suffer from neglect. Bearings in the linkage seize due to petrified 50yr old grease and begin turning on the bolts instead of moving freely. Torque tubes, especially the early ones, were known to develop cracks and not provide the required downlock tension. If the gear is inspected thoroughly, worn parts replaced, stiff bearings cleaned and re-lubricated and the rigging set to spec, the 310 can take quite a fare amount of abuse with no problem.

I own, fly and maintain a 1961 C310F so I am quite familiar with its pitfalls and requirements.

[/quote]
Glenn what is your basis for these claims?

I own, fly and maintain a 1961 C310F so I am quite familiar with its pitfalls and requirements.[/quote]

30 years of commercial maintenance experience, and also industry data from insurance claims, and ASIAS database reports of gear failures. Twin Cessnas are at the top of the list. And you'll find plenty of videos of C310's landing on their noses, due to nose gear problems.

You should also check the gearbox mounting rib. You'll find cracks where it joins the other ribs if the plane has been abused in cross wind landings. I found a C340 landing gearbox rib cracked halfway across during a pre-buy.

I bought a ‘76 R model new - flew it 25 years and 6,600 hours - never a gear problem and no cracks calling for the side race kit. Then flew a ‘69 P model for 14 years - it had had a rough life in Alaska prior to my owning it and did require a side brace kit but never had any gear issues. Flown properly, the gear is very robust!

I have owned three different early sixties 310s and loved the reliable IO 470s, speed, efficiency, cabin space, wing lockers and flight characteristics.

The biggest pitfalls are the corrosion issues. Don’t buy one without removing the firewall sealant at the engine mount rails for a close inspection. The stainless firewalls cause the mount rails to get dissimilar IG corrosion on the rails that are usually not cost effective to replace. They are also prone to corrode on the back of the upper and lower rear wing spar cap angles in the flap wells. Also the aileron wells but not as prevalent. Also look at the rear spar caps in the vertical fin in the exposed rudder well. Sometimes the corrosion will present itself as a smooth bump starting from the grain of the angles. And the exposed nose interior above the gear. They don’t do well in a humid environment.

I've had a number of 310s, and found them roomy, efficient, and relatively easy to maintain. I have a Lance right now, however. While you ruled out a Navajo, you might consider a 401. They have about the same maintenance requirements as the 310, with approximately the same hourly cost. But they're turbo'd, and have a great deal more cabin volume (and seat 8). The useful approximates the PA-31 at around 1900 pounds, with standard 20 /side aux tanks has a 4.5 hour endurance. I've owned three of them,, and loved them. They're basically a short nosed 402, and can be bought for less than a 310. They've always been kind of a sleeper on the market.

This is a great discussion. Someone at my airport is purchasing a 310R and considering a partner. Any ideas what the range of realistic operating costs should be? I understand there's a lot of variability here based on airframe and shop, but some estimates would be helpful.

Base Annual
Other Yearly Repairs or Hourly Repair Reserve
Engine Reserve
Fuel
Oil Changes

I have always thought a T310Q or T310R would be a good upgrade from my turbo Mooney. I like the turbo to meet the high MEAs out west and climb out of icing conditions. That said, given the repetitive AD on the turbo 310s, does the cost and inconvenience of doing the AD (every 50 hours or 3 months, I believe) outweigh the benefits of having the turbo 310? Would it better just to buy a normally-aspirated 310 with deicing equipment? Anyone out there with real world experience with that AD?

Thanks

Ethan,

I had a de-iced (not FIKI) T310R for 23 years. Needed the altitude capability for the MEAs as you mentioned, and to climb out of icing. Central Rockies 16,000 westbound, 17,000 eastbound; so if you start picking up ice you need to be able to get to FL 220. Not often, but often enough, for me. Also the single-engine ceiling (at max gross) of 17,400 was very helpful, once.

The exhaust AD is common to all turbo'd twin Cessnas. Every 50 hours a visual inspection, during the oil change, takes 20 minutes. If you start with a good, solid system, not a big deal. At the annual, a pressure test, which should be done anyway. And at engine overhaul, send the exhaust out for IRAN. Overall, not a big deal, and turbos well worth it, IF you need the all-weather year-round capability out here in the West.

Cruise 200 KTAS at FL200 on 36 gal/hr total. Just make sure you have enough oxygen, and that the cabin heater works well. I carried hand warmers and Sorel boots for just in case -- needed a few times!

Overall a beautiful and capable plane. Just make sure you start with a solid corrosion-free example. Good luck!

Compliance with that AD should be mandatory for every turbocharged airplane in existence. 50 hours/30 days (latter of) is the most I want to fly an airplane with the extreme conditions that a turbocharged aircraft operates in.
The other five or so sections of the AD are also important. Compliance is relatively easy, but documentation often becomes jumbled up based on many of the aircraft I’ve seen..