Single vs. Twin

capt_zman

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Just wanted to check in and see what people thought about the old single vs. twin theory.

I for myself am all for the twin engine airplane. Redundancy and speed far outweigh the maintenance drawbacks. As for flying safety, lets hear some opinions.
 

bobbysamd

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Twin pros and cons

You usually have two of everything on a twin. Two alternators, two fuel pumps, etc. Hopefully, and more importantly, two vacuum pumps. In other words, double the worries. Bad fuel in a twin and you lose both engines. The average light twin glides like a rock. You can always install an auxilary vacuum pump on a single

A big misconception about a light twin is more safety. Notwithstanding twin-engine operation concerns, e.g. flight near Vmc, losing an engine means you buy time to maneuver for safe off-field landing, if you're not near an airport. I remember how we practiced engine-out procedures in our Seminoles at ERAU-Prescott. It was amazing how quickly we lost altitude. Of course, bad technique made it worse.

Lose one on takeoff and maybe you can struggle up to altitude to fly a full pattern to land. On a hot day, you may again get more time for that off-airport landing.

Speed depends on the airplane. I recall that an A36 Bonanza cruised almost as fast as a Seminole. I also recall that our retractable Skylanes had a high cruising speed.

Even with the possibility of losing two of everything, the percentages of that are remote. I'd say a lot depends on the mission, but, you're probably safer in a twin that is operated safely and properly.
 

bigD

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Hmmm....I really think it'd all boil down to my financial situation. I like the redundancy of a twin as well, but can I realistically justify paying a lot more in operating costs for the piece of mind of the second engine? If I had about $150K to spend on a plane, I'd probably look at a nicer 6 seat single as opposed to an older light twin. Buying a twin on the cheap would probably eat me alive come annual time.

But if I had the cash, then yeah - I'd buy one. But realistically, unless I hit it big somehow, I'd be buying a 210 or A36. Sure, I wouldn't have the 2nd engine, but I'd rather sit in a Centurion or Bonanza than a beat up Apache or Seneca I.
 

bigD

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Bobby makes an interesting point about safety. I feel that a twin CAN be more safe than a single as long as there's a proficient pilot at the controls. Trouble is, I bet a lot of light twin drivers don't practice emergency procedures as often as they should, and that makes them more dangerous should an engine pack it in.

As far as redundancy, the real potential life saving items on a light twin are the second engine, and another vacuum (or pressure) pump. Most heavy singles have standby pumps anyway. Another alternator is nice, but if I do my job, it certainly isn't a dangerous situation to lose one. I'd land just the same if I lost one in a twin or a single.
 

bigD

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Oops...posted twice here. Sorry about that.
 
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aero99

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Guess it matters what kind of mission the person answering needs, wants, or uses.

If operating cost were taken out of the equation, a twin any day for the obvious reasons the other posters listed.

There are not many signle engine planes (piston) that can really carry six people, so singles have a very limited mission plan (in my opinion) for business use.

Now if I had the choice of single turbine or twin piston I would take the single turbine any day for safety purposes and reliablitity.
 

bigD

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It's tough finding a single that can compete with a B58 on all fronts. A Saratoga will carry a bit more payload than a B58, but it's much, much slower. An A36 is almost as fast as the B58, but it's barely a 4 person plane with the tanks full (the one I fly can carry 679 pounds with full tanks). I don't know the specs of a 210.

Trouble with the B58 is that you're looking down the barrel of a quarter mil for a mid to late 70's model in good shape.
 

hyper

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Patmack18 is correct. More people die in engine failures with twins than an engine failure in a single.

I used to tell all of my new multi students to only pursue the rating if they can afford to stay current. If you're in the profession, than you have your mandatory 6 mnth check anyway. But I saw too many privates that would come to me for a BFR or checkout and would die if they actually lost an engine for real, with their present proficiency level.

Under that condition and money available, I'd go with a twin. But it's all about the money, isn't it?
 

Rvrrat

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Type of mission is imho the driving factor, terrain considerations next. Propper training and proficiency is a must regardless of equipment, for example, one only needs to mention the MU2; capable aircraft & safe if one knows the ship and has been trained well, same for any other plane. After that it's a matter of what one can afford.
 

rumpletumbler

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hyper,

So did you sign them off with a level of proficiency that sentenced them to death?

RT
 

tcoll777

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twins

The second engine takes you to the grave site!!!!!!!!!! Unless you are PROFICIENT.......than it's all about the twin safty....
 

bigD

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If I remember correctly, the actual rate of engine failure related accidents is lower in twins, however if an accident DOES happen, you're much more likely to die from it in a twin. Which to me points to proficiency being the name of the game.
 

hyper

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BigD,
You're right. That's a more accurate statement.

RT,
I'll reiterate although you knew what I meant. No, I did not. The "present" wording was in respect to their level of proficiency at the time that they came to me. Get a little more time under your belt and you'll understand.

see ya
 
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jetdriven

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there are many times I feel safer in a single than a twin. Example, a takeoff in Santa Fe, NM or Gunnison, CO. The air density is above the limit for most non-turbocharged twins (B-58,B-55, duchess, semonole, etc.) So on takeoff at low altitude, an engine failure results in a crash landing. Same with a single. But a twin has at least TWICE the chance for an engine failure. Plus the crash would be less survivable, more mass crashing at a higher speed with no engine in front of you to bear the brunt.. So in that case I would rather be in an A-36 than a baron.
Flying hard IFR with 200-1/2 or at night (or both) I prefer a twin, because of the redundant systems and probably anti-ice and better performance. Same with night flying, no better feeling than two continentals humming in sync, all the needles matched up. OF course, if you're not current, then it all goes out the window. You're better off in a J-3 cub. It is the safest airplane ever made. IT CAN JUST BARELY KILL YOU..:D
 
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