Anyone with experience in older C310's

[Flightist]

The Flight School I work at may get a 310A model for doing flight training in. I have about 10 hours in it now. It seems like a real nice machine to me. I am likely to get my MEI finished up with it. I would appreciate information that anyone might have on flying and instructing in a 310, especially one of these older ones.

Thanks Much Jim

 

[bin LAAidoff]

Dont have your students manually extend the gear.

It's nice to do on a checkout, and on aircraft like the Apache, or Piper singles, Cessna retractable singles it's nice, but on the C310's I've seen, (and the one I owned used for instruction) the manual extension has a very weak link:

Electrically extended gear. Motor drives large cog type gear (10+ inches) that lives under the floorboards. When manual extending, extending the manual extension handle disengages the electric motor (in case it's seized). Two helical gears, about the size of a quarter are conected to the top of the manual handle. As you crank that handle, rotation is shifted 90 degrees, at least 4 times. Those little helical gears get torn apart. I've replaced them twice during annuals.

So...on my checkouts, I'd take a student through the checklist, have them put the seat back (helps alot!), extend the handle, then "simulate" cranking. Otherwise, you will end up striping the helical gears eventually.

Nosegear is a weak link on CE310 up to the early P models. Wheelbarrel landing very bad!!! Probably only get one.

 

[Dan CFI/CFII]

first suggestion: make sure that exhaust is in good condition. Seriously, that overwing exhaust is pretty, but it could end up grounding your airplane for months if it needs fixing...

I've never flown older than a D model...

Don't take students into IMC unless you are VERY comfortable with the panel and it's shotgun layout. Even then, I'd make them play under the hood a good bit in clear weather before hitting the clouds.

Especially IMC--watch the pitch up with flap extension, it is more pronounced on the older models.

Make sure the oil dipsticks are secured. If they come loose (and on the older models they can and are hard to tell if they are locked) you will coat the plane in oil. Not to mention start to lose the oil pressure in that engine...

Teach everybody to climb faster than Vy, you need to keep the engines cool to keep the plane flying much (good advice for any plane).

Make sure the fuel selectors are in good condition, the mechanism can get enough slop in it to make it real tough to be playing with in flight.

Landing lights need to be extended once the plane is pretty slow. Early models (A included I beleive) have a limiting speed, I'd take a few mph away fromt hat number. Those mechanisms can be very expensive to replace, and can keep the plane grounded a long time as well--you don't want that as a CFI.

Ditto the nose gear--make sure it is checked out by a knowledgeable Twin Cessna shop.

Make sure there is a good checkout with the plane. The fuel system gives folks fits, the janitrol is probably new to most renters, etc... The other big thing is that the plane eats up ground a lot faster than most anything they've probably flown up to this point. The jump from Arrow to a 310 is HUGE. The jump from Seneca to 310 is just about as big.

I love instructing in 310s (its sort of my specialty around here), but watch out, it can bite ya.

Dan

 

[Flightist]

Bin Laaidoff

Thanks for the advice on the maual gear extension. Any components (bolts,bushings,etc.) to look at for wear on the nose gear? Any advice on the maneuvers, handling characteristics, etc. that would help me in prepping for my MEI? Looking at what you fly now, I'm sure it's been a while, but any other advice would be great.

Thanks Jim



Thanks Dan

Appreciate the reply. Are there any points of failure to look for in the exhaust. I found out about the loose dipstick problem already - made a little mess. This model didn't have a little hook bracket like I saw in a newer model - just a press-in fit. The vacuum worries me a little - it shows only 4". Looks like someone hand drew 2 lines to indicate that was the correct range. Could that be normal?

We've been fighting to get the low speed circuit of the carbs to settle down. The A&P working on it got it doing better but it still seems to run rich and have an excessive RPM drop during the Mag checks. Needs some more work I guess.

Any advice you can give me towards preparing myself for my MEI in this thing would be appreciated. Like for instance - when I did my ME in a Seminole we did the VMC demo with full aileron and rudder into the good engine with stall horn, buffetting, etc. all going on before we recovered. Can you get away with that in the 310 or do block the rudder or lock the controls and recover at a faster speed than VMC? How much power do you use in power-on stalls? Speeds in the pattern? Speed on final with the short field? The manual this thing came with isn't quite as complete as a 1970 model I flew. In any case thanks alot for taking the time to help me out.

Jim

 

[Dan CFI/CFII]

Big bore continentals always run rich on the ground. Lean the thing.

I always blocked the rudder about 10 knots above the stall for Vmc demos. Do them real gentle, if you simply slowed to Vmc and cut an engine, you'd get a REAL Vmc demo--scary bro.

The bearings in the nose gear tend to get killed by hard landings--check them. Make sure all the microswitches and motors are clean and correctly rigged.

Power on stalls: I always used 23 Inches, but that was just a number I like.

Speeds in the pattern: Dirty, I do 140 (should take you about 18" MAP). 130 on base, 115 on final. For short field I might take it down to 100 mph, but not on a bumpy day. I'd just as soon go faster and bleed the speed off over the runway.

Exhaust: the augmentors are very prone to corroding from the inside out, and when they do you've got a spar with hot exhaust gas blowing on it. When some buds of mine had to replace them, the Cessna Owners Association said it should run around 5 grand a side, quite possibly 10 a side--IF we could get parts. If you see any cracks, patches or exhaust stains outside of the augmentors (like on top of the augmentor nacelle)--time to pull the exhaust assembly out of there to check it.

The lines on the vacuum guage can be hand placed, that's fine. The real question is where are they SUPPOSED to be? 4 InHg doesn't sound too bad. If the A model has the four position selector, is that what the pumps are taking in or what the DG/AI are seeing?

Dan

 

[Flightist]

Thanks Dan!

So that's what that position switch does.

Did you have any problems with the gears on the manual extension. Do you suggest not using it. We were going to jack it up and test out the gear operation. Do you think that would be a good time to test out the manual gear extension?

When I did Power-on stalls with the Seminole we did them at 18" M.P. Is that being woosie? Should you have the ball in the Turn Coordinator centered? offset a little?

Your speeds in the pattern sound pretty much like I was using.

Thanks again. I'd like to ask you more when I have more experience and can ask more intelligent (or useful) questions!

 

[bin LAAidoff]

top of the trunion, not easy to really inspect, but I hear that's where the nose gear failure begins. Hairline cracks, but I doubt they show on a visual. Perhaps dye penetrant, but the nature of it would require removal for inspection. Trust thy mechanic, and dont let anybody land nosewheel first.

The angle of the nose strut I hear is what causes the stress. Late model P's and beyond have a strait down nose strut, others angle forward.

Never flew the carburated models. understand the F and earlier (58?) were actually even more slippery than the 68 N model we had. Flying by "the numbers" did wonders for me, and students. If memory serves, 17", flaps 20, 120 kias on ILS (15" in the F or C model). Landing Assured, full flap. slows to a nice approach of around 100 crossing threshold. Granted a bit different from the "stabilized approach", but very stable. Not too different than a common gulfstream "quiet flying" of landing flaps below 400agl.

I loved the 310, and if I think of anything, I'll pass it along. Spose emphasizing the difference between an alternator vs. generator could be important. If flying IFR, waiting for release, Idle power really drains the battery.

I tended to not use the landing lights except at night (about 75fpm on a drag demo), and never used them for takeoff. My logic is they were placarded "landing lights", and in an engine out, I'd forget to retract. At 150fpm climb, suddenly those lights could cut you down to 75fpm. So much for "Operation Lights On". A model lights are much bigger than N, so probably even more drag.

While rambling, I finally remembered the BIGGEST achiles heel, and ultimate demise of our C310. Most gear switches are 3 postion! Down, Neutral, and Up. Why cessna did this, I dont know. There were no procedures calling for the middle position. Perhaps because it is electic? Turn off the moter if a microswitch fails? Well, ours had a club member do a gear up touch and go. He touched the switch, but must not have checked the lights. The middle position. Club 310K geared up in Reno. Kudos to the unlikey pilot for at least being honest and saying "I f-d up, landed with it in the middle position." At least others can learn from his mishap.

Easy on the brakes. Probably goes along with what Dan said about eating up runway. We'd get 150 hours max on tires in the airplane we had in a flying club/training. My buddy with an F model and same tires would get 300+ hours. Flat spots on ours.

One of my favorite oral questions: Crossfeeding fuel-- running left engine and right engine off the right tank. Why will left tank quantity increase eventually? Dont know if the carb models do this as much, but the IO-470 mechanical fuel pump takes more fuel than it needs. Regardless of the fuel valve positon, the excess fuel returns to the engine side, main tank. So I suppose "technically" you can transfer fuel! Not much. That's why on the aircraft with aux tanks, you'd better burn 8 gallons or so from the mains first. Otherwise, you are p*ssing fuel out the vent. You wont see it, but she's going to take more fuel than you thought at the pump.

The twin cessna flyer, or some club/newsletter like that always had great info.

Happy flying. I'm getting a tear in my eye already and missing my old 310. That ok, I've got my eye on a 185, and I'll be posting a request like yours if I get get my hands on one!

 

[Dan CFI/CFII]

The older ones aren't necessarily slicker, but you can't put the flaps down at such high speeds. In a P model, pull the power to idle slowly, and at 500 fpm of descent you'll still be too fast to put down the flaps (if you start from cruise).

I like to use that first bit of flaps just to add some drag so you can get the plane slowed down without getting the engines too cool (in fact, when I start my descent, I'd pull the power to 20 InHg, and do the rest with gear and flaps until I am on pretty short final).

I've never had a problem with the manual extension, but then, I've never done it in flight. I'm just too worried about something not disengaging correctly and the handle trying to spin or something--seems like it can really mess up some wrists. But yes, I'd definately swing the gear a few times on the ground--while carefully checking the rigging. Again, if the schools A&P doesn't know much here, don't hesitate to take it to a real good twin cessna shop. My students bought a 310 and one of the Mx shops told them they really needed to go through the gear. They asked me about it, and I said "I don't see anything particularly wrong there." Well, they decided to check it, and found it was really, seriously in danger of breaking (as in, off). I'm man enough to admit I'm no expert--make sure your A&P is.

The gear switch comment is right on. I've only flown one 310 (a 1960 D model) with that stupid switch on it, but it is really easy to miss. The plane isn't so much of a rocket with the gear down and locked. Make sure they are looking at those lights.

And the brakes--roll till the plane is slow as possible. They get hot enough as it is. I'd happily use up 7400 feet of runway if it meant not using up the brakes and tires. I've generally been able to get a LOT more than 100 hours out of tires--so keep them feet off them brakes.

I'm missing flying too (and especially missing flying 310s right now). <sniff>

Dan

 

[hydroflyer]

You might also want to check out sporty's for the AOPA Safety Review of the Cessna 310. It is around $30 and has about 250 pages. It includes accident statistics, accident briefs, common problems to watch out for in each model, how each model changed and even a training outline, although it doesn't have any info on stalls or slow flight type of stuff, just Vmc and single-engine operation. I thought it was pretty good, not sure about the $30, but I personally want to know as much as I can about the airplane I'm flying.

 

[Flightist]

Thanks everyone for some very useful information! I'm so impressed with what a great resource this site is. There is always someone with the expertise you need willing to help a rookie like myself.

Jim

 

[310]

I have a C model 310- 1959. io470d engines 260hp /side. The gear switch is three position for a reason. If the gear were not to deploy, you want to put the switch in the center position before hand cranking the gear down - so if its a motor problem, its does not spin the handle in your hand and break your hand. Also the only way to do a manual extension without pulling a breaker. (If you do a manual extension, crank to stop, stow handle, select gear down and verify green light.)
Flaps -first ten degrees at 160mph max. (less is better)
rest of flaps at 140mph(I use 130-135)
Gear at 140 mph max(I use 130)
Landing lights 140mph max (I use 130)
Take off at night with taxi light(on nose wheel)
Make small and slow power changes. Keep power in the green.
On injected models don't go full rich on approach with boost pumps on- can go too rich and quit. (experiment at 3- 4000 over airport)
Aux fuel for cruise only- no descents or climbs on aux)
Fuel comes out of aux at about twice the burn rate with the remainder going to main on same side. ( I stagger use of aux fuel- don't run both engines on aux at a time- thats just me)
Allow 5 to 6 nm per 1000 feet for descent to pattern alt from cruise alt.
75% is a little too much power in cruise for good engine life on injected models. Cowling is tight and engines produce more power per cubic inch of displacement than most GA engines.
A 310 does good on one engine- mine holds 4500 ft on a hot day with one a 75%(24/2450) but be careful about getting to dirty way out and down low- gear and big flaps has alot of drag.
It goes from really slick to really dirty with gear and flaps. (Flaps are 9 feet per side, split design and large chord, 45 degrees full down)

On downwind try this- have speed at 110-115 mph, power 17/2350, gear at 10, gear down- start adding flaps for descent, check gear green on downwind, fuel on mains, turn base, check gear green, add more flaps- don't touch power until ground effect, turn final and check gear green and add flaps as needed make small power changes only if you have to. Slow to Vref ( 95mph at gross) Pull some power out in ground effect. Requires a small pattern.

Remember a gear up probably means a total loss in a old twin(cost of repairs exceed a certain percent of insured amount)

Don't get slow and dirty on final and pull all the power out. More the one 310 has hit so hard that the wings bent outboard of the gear.

The gear is electric and very slow- so I was taught to leave a finger on the gear switch until getting a green light.

I get up to 170 knot true speed - up higher at 21/2350.

 

[310]

A little 310 history.
310 and 310B pressure carb O-470 continentals of 240 hp
310 came out in 1954. A Air Force U3-A is bacically the 310B.
310C was 1959. IO-470D of 260hp. Only model with straight tail and injected engines. 262 were built. Lightest weight of the 260hp per side models.Same as U3-B- one at Wright Pat museum
310D -1960 swept tail and bob weights added to elevator cables- alot of these were modified(the bob weights messed up handling)
Some letters were skipped.
Tanks were canted in early 1960s.
Only Q and R models were built multiple years.
Some Qs were 260hp some turbocharged- I don't know HP.
R model- nose extended- nose gear shortened, Changed to 285hp IO-520 Continentals.

If you can find a old one without corrosion behind engines due to exhaust augmenters, there is a STC to change to underwing exhaust. Mine was done a long time ago.