PA30 Twin Comm, Aztec or Seneca I?

[Fuji Abound]

Have you had to sit (as an adult) in the back row for any length of time?

Now that is very true.

Also single engine climb is pretty good - definitely not in the marginal category.

[bookworm]

However, 3 hours flying is 21 gallons per side i.e. 42 USG total. Can be 18 a side if I am careful or even less with a tailwind.

You must have some heavy friends.

Light friends, heavy aeroplane. With 4 x 180 lb people and 70 lb baggage (excluding the emergency equipment) I get 38 USG in. My rule of thumb is 14 USG/hr (which includes a contingency) + 4 USG excess for t/o and climb. So that's 1.75 hours to destination and alternate + 0.75 hr FRF.

[DFC]

The interlink on the controls just means you have to be a bit more adaptive in strong winds but has never been a problem

The interlink on the controls means that when you apply left rudder, the control column rotates left and thus applies left down aileron.

This means that when you are landing in a right crosswind, when you kick it straight with the left rudder you will get left roll caused by the yaw and increased by the input of interlinked aileron.

It is not something that you can be adaptive about and the later models with this removed have higher crosswind limits.

---------

Bookworm,

I would not describe 3 13 stone friends as being "light".

Surprised that your limited by so much.

Thus you must spend a lot of time with the aux and tip tanks empty. Does this cause a problem with the bladder in the aux tanks drying out?

I can't believe that you can only carry round about 1/3 of the aircraft fuel capacity when going flying. I have not had such a problem. OK, not full tanks and full seats but I am sure we could carry more fuel than that.

Have you had your aircraft weighed recently?

Regards,

DFC

[SNS3Guppy]

If I were in the market for a light twin personally, I'd be shopping for either a Cessna 310 or a Beech Travel Air. Both can still be had for good prices and have much better performance in my opinion. I wouldn't consider either of them a six place airplane, of course...but then one of the only light twins I'd put six people in would be a Twin Commander.

Think about your mission. Sometimes people start looking for an airplane based on the largest amount of people they might carry, when 90% of their missions will be solo. If that's the case, you're better buying something suited to the majority of your flying, and rent or otherwise improvise when the occasional need comes up to do more.

[On-MarkBob]

There is another twin, so far not given a thought here. Generally cheeper to buy than the others, even when fully equipped with de-icing equipment. Good short field performance, good range, six persons (just) four with baggage, easy passenger access (with the exception of the very rear seats), reliable and just as cheep to maintain as the Seneca and certainly cheeper than an old Aztec. Intrested? Not everyones cup of tea mind you, but if its twin engine safety and reliability you want above anything else then take a look at the good old Cessna 337 Skymaster. The Twin boom Push-me Pull-you.

[SNS3Guppy]

The skymaster is okay when both engines are running. It's not when one isn't. It also puts you in a position between two weights with fuel all around, and hot exhuast at each end, a considerable amount of noise, and one way out if the cabin's bent.

[S-Works]

This means that when you are landing in a right crosswind, when you kick it straight with the left rudder you will get left roll caused by the yaw and increased by the input of interlinked aileron.

It is not something that you can be adaptive about and the later models with this removed have higher crosswind limits.

Dunno about that mate, it may be a difficult concept for you but I have managed for well over 500hrs to put it down in some howling winds. I guess it's what you get used to.

[bookworm]

Surprised that your limited by so much.

Thus you must spend a lot of time with the aux and tip tanks empty. Does this cause a problem with the bladder in the aux tanks drying out?

On the contrary, I very rarely put 4 people in the aeroplane.

Have you had your aircraft weighed recently?

Much more often and recently than most aircraft, I think. 2610 lb. I obviously can't speak for the aircraft you fly/flew, but I get the impression that a lot of owners/operators do a lot to avoid having their aircraft reweighed for fear of bad news.

[Fuji Abound]

Dunno about that mate, it may be a difficult concept for you but I have managed for well over 500hrs to put it down in some howling winds. I guess it's what you get used to.

Luving it.

[Fuji Abound]

What are you going on about?

I thought with 500 hours on type is was a sound comment.

[S-Works]

In which case I humbly apologise. Perhaps I still have a raw nerve or two.

[Fuji Abound]

No problem, and no need.

I appreciate you dont agree with my approach, but hopefully it is not something we ever need to really fall out over.

[AC-DC]

Bookworm wrote:
...most Twin Coms with reasonable kit are not capable of carrying 4 normal adults on a typical tour. With 4 adults plus light baggage and a dinghy, you're down to about 3 hours to dry tanks.

I have a problem with your numbers.
If you have tip tanks you can carry 90gl but your W&B shows only the 60gl in your main tanks (keep your AUX empty), the tip's fuel is FREE weight, that is 180lbs that you can forget about. 90gl @14gl/h should give you 6.5h to empty tanks or 1040nm. As far as I can recall your aircraft has tips or am i wrong?

ACDC

[bookworm]

Haven't got the spreadsheet in front of me but from memory...

I'm assuming the tips are carrying at least 125 lb of the fuel, hence the MTWA is 3725 lb. With the tips empty, I'm down to 3600 lb MTWA

2610 lb aircraft
720 lb people
70 lb baggage
20 lb anti-ice
75 lb emergency equipment (mostly the 4 man dinghy), tools, cover etc.
230 lb fuel = 38 USG (of which at least 21 USG must be in the tips)

Total 3725 lb.

[TwinkieFlyer]

2610 has to be a turbo Twin Comanche. A non-turbo would be more like 2450 to 2500. Gross with tips is 3725 IF you have at least 125 pounds fuel in the tips. Otherwise gross is 3600. There are some Robertsons with gross of 3800.

A Twin Comanche is a great airplane IF you don't get into icing. With only 160hp per side, it isn't going to handle ice very well. It will do 165k easily on 16 US gallons/hour, and 155k on 14.5, and that is total, both engines.

A non-Trubo, 5:15 total fuel at 16gph.

And no, it doesn't cost twice as much as a single to run, the reason is the systems are so much simpler than most twins.

If you want to carry a big load and deal with some ice, buy an aztec, they may be ugly, and they burn a lot of fuel, but they will fly through a lot of messy weather.

[aztruck]

Aztec, but get a good one and look after it. Rock solid in cloud, almost the same payload as a Navajo, built like a tank and handles grass, mud and gravel no problem. lowest fatal accident record of any twin. bit noisy in the cabin - get anr headsets for passengers and yourselves.
Get a good E model, and stay clear of the turbo ones.
500 m wet grass, 6 up into st Mary's scilly isles, Stuttgart/London night IFR 6 up...takes it all in its stride. Bit thirsty. Nip over to alderney with those big fat longrange tanks and fill her up!

[bookworm]

2610 has to be a turbo Twin Comanche.
...
A Twin Comanche is a great airplane IF you don't get into icing.

Nope, not a turbo, but with de-ice (boots and prop anti-ice).

[AC-DC]

Bookworm

Your aircraft is an heavy one. You can store 30gl in he tips (180lbs) that can be kept out of your W&B. In any case, flying 4 men is always hard. I did it but had to leave the cover behind, then I was 20lbs below Max.

[bookworm]

Your aircraft is an heavy one.

That may be the case. But the only other person I've known who has bought a Twin Com also got a nasty surprise when he got the real W&B sheet. The message is clear -- weigh before you buy.

You can store 30gl in he tips (180lbs) that can be kept out of your W&B.

That's a strange way of putting it, and numerically incorrect. The installation of tip tanks increases the MTWA from 3600 lb to 3725 lb, with the condition that any weight in excess of 3600 lb is fuel in the tip tanks. So in essence you can have 21 USG (125 lb) in the tip tanks without having any impact on the passenger and baggage load.

[DFC]

That's a strange way of putting it, and numerically incorrect. The installation of tip tanks increases the MTWA from 3600 lb to 3725 lb, with the condition that any weight in excess of 3600 lb is fuel in the tip tanks. So in essence you can have 21 USG (125 lb) in the tip tanks without having any impact on the passenger and baggage load.

Now that is 1.5 hours at normal cruise power settings.

Thus one could use that fuel for a 1 hour diversion at long range cruise and a 45 minute hold at max endurance power all including contingency.

That leaves all the rest of the fuel you carry to get you to destination.

There are very few such aircraft where the limiting factor is not the endurance of your bladder!

Regards,

DFC