I'm not.


That is the FAA, not me.

I think a case could be made that a single turbine is reliable enough to go to FL410. But them ain't the rules.

You also have to understand engines shutdown in flight for all sorts of reasons that aren't the ENGINE's fault. Fuel system faults, pilot error, ash, fuel exhaustion, intake icing, etc. So while engine failure of 1 in 10,000 hours seems far too often, it isn't once you consider ALL the possible ways an engine can shutdown.

And, yes, many (but not all) of those engine shutdown causes would affect BOTH engines in a twin. The major reason to make it a twin is to meet FAA rules to allow access to FL410. Engine reliability is a secondary concern to that.


PC12 has no chute and no fatalities from engine failure. WAY more of these flying getting WAY more hours the the SF50 fleet will ever get. The FJ33 will probably be more reliable than the PT6 (for one, no prop and associated parts).

Mike C.

Running out of fuel will shut both of them down every time, I'll give that much.

Back to the topic, I can count on one hand all dual engine turbine shutdowns during last 10 years. Really, what you are saying is that twin actually needs a chute more than a single due to much higher impact forces during an off airport landing

Ciholas Institute of Aviation: Cirrus SF-50 vs. MU-2 passenger survey results:

What do you think about the pilots of the respective aircraft?
SF-50: Why do all the pilots carry man purses?
MU-2: Does Mitsubishi sponsor pilot gyms? Those guys are all twisted steel and sex appeal.

What is your opinion of each aircraft after flying as a passenger?
SF-50: Small and uncomfortable with lots of squeaks and rattles. Marketing brochures always flying around in turbulence
MU-2: Flying bank vault, the hammer of the gods, my prepper buddies know where to go when the SHTF!

How do you feel about one engine vs. two?
SF-50: One is fine, I just take 5 Darvocet and two shots of Whiskey before each leg
MU-2: The two engine reliability is statistically perfect. Any problem would be on par with winning the Powerball three times back-to-back.

Would you have any issues going overwater?
SF-50: None, if it was disassembled and put in the cargo hold of a 747
MU-2: We heard that the hull converts into a submarine in the almost impossible event of a water landing, just like that Lotus in the James Bond movies.

(Woman passengers) What would you say to the pilot given an opportunity?
SF-50: Can I borrow your lip balm?
MU-2: You make me want to be a better woman.

So there you have the FACTS that everyone has been asking for.

V tails for drones is more viable because drone CG ranges can be tightly controlled (thus reducing trim drag), drones require less radar signature (V tails with angled surfaces do better naturally), drones don't require good stability (no humans to make sick, computers to actively augment stability), and because drones are already electronically flown so control surface mixing is not an issue. Also, drones have less safety requirements, so the issues of flight control system redundancy don't come into play.

Thus we see more use of V tails on drones than on "regular" aircraft.

As far as I can recall, there has never been a part 25 certified V tail airplane.

Have there been any powered part 23 certified V tail airplanes?

The 35 Bonanza was CAR 3 rules, not part 23. Surely it wasn't the last powered V tail design certified?

In your list, only the F117A is manned and exists, and it was willing to sacrifice all sorts of aerodynamic principles to achieve the radar stealth. It clearly isn't an efficiency play.


Not for the same stability requirements. This has been studied and tested.

From NACA report 823 on V tails:
The analysis indicated that a vee tail designed to provide values of stability and control parameters equal to those provided by a conventional tail would probably provide no reduction in area unless the conventional tail is in a bad canopy wake or unless the vee tail has a higher effective aspect ratio than the conventional vertical and horizontal tails.

So assuming 1) you don't make a really bad fuselage with some sort of bad wake over the tail (which is easy), and 2) you are willing to use the same tail surface aspect ratio (you can't compare a slender vee tail to a stubby conventional one, for example, that's not playing fair), then there is no advantage in wetted area for the V tail.

If a particular V tail version has less wetted area than the equivalent conventional tail, then the designers accepted less stability as well.

If you did stability tests on the 35 and 33, I am pretty sure you will find the 35 is less stable and the 33 could have its tail reduced to match.

Mike C.

Been done. You realize we have all been here a while right?

Cool. Show us the numbers from the testing.

Mike C.

So you are saying that Beech designed F33A with a tail that's too big?

Cool. Show us the numbers from the testing.

Mike C.

33 too big or 35 too small is subjective. It all depends on what criteria you wanted.

For the same stability, you need the same area. This is actually quite obvious since what gives stability is damping and damping is a function of surface area interacting with the air.

Mike C.

Your friend, too.

I'm not going to try and guess what you are referring to.

Link or it didn't happen. :-)

Mike C.

I have been reading this thread from the beginning. I don't see Mike's agenda but maybe I am missing it....
The more I read, the more this image comes into my mind.
This thread reminds me of the gun debate where facts really don't matter that much.

I matter so little I can't even get feed back on the King Air X tail mod...

Jeepers I feel so unworthy

I'd be glad to help you out Mike.

In return, I'll ask you work on communicating respectfully with the rest of us BTrs. I'm not sure its intentional, but you don't come across very cleanly. We have a great group here....for a reason. Let's keep it that way.

To the yaw issue, Barry Schiff did a test and wrote an article in the early '80s (Bonanza Besieged? iirc) where he fitted 33/35/36 models with accelerometers. While the test showed the 33 was slightly better than the other two models on paper (yes, better than the 36), he noted that the difference between the 33 and 35 was imperceptible from the pilot seat.

Best,

Jesse, Which post of Mike's wasn't respectful? I cant read through all 88 pages again and I must have missed it the first time!