Capt_CrashN_Burn

..or whatever your winter solstice celebration of choice is. Meh! whatevs.. Dec 25 is a Pagan holliday anyways.

I thought this was only supposed to happen in Bonanza 35's. :-/ Sorry to hear about the good doctor.

Did anyone notice that the OP has only posted once, then split??

Quote: donshapansky Hey, Parker I've sat in one but it was over 2 million, an older TBM has useful load issues about the same as the JetProp with no better speed and a lot more money. ?

So sad to hear about this. It just goes to show that each and every day we get to spend on this earth is a gift, and should be treated as such. It's a good thing they didn't leave orphans behind.

Quote: carusoam Reality strikes... Crash, I think what you have been told about prop speed and speed of sound (although correct) has been simplified to explain why the RPM range is chosen for a particular prop. It sounds more mysterious than the more mundane actual reasons. So my guess is.... somebody at the airplane factory noted prop speed vs. effectiveness (angle of attack too). Engineers like to test this kind of stuff and write long reports that go with that. They (engineers) need to answer stuff like: How much pull can I get out of this prop from take-off through cruise? and How is this best accomplished? At take-off, with no airspeed, through rotation and climb, 2,700 rpm must be the most pull available to get the plane off the ground quickly and safely (including safely for the engine). Realisticly was it 2705 rpm or 2690.32 rpm that gave the best performance? Again somebody simplified the system to help the pilot not need to be a flight engineer. Another factor of safety is added to the system because of the accuracy of the rpm gauge in the aircraft may be off 10s of rpm or worse. During cruise, the same prop selects an RPM that is comfortable(lower vibration), an efficient match to the airframe (speed vs. mpg), economical (to make, sell, operate). Ordinary propellers are clearly not efficient at anywhere near supersonic speeds (prop or airplane). Compressibility of air makes it far from ideal, and gets further away from bernoulli's principles as the speed of the system increases. We want air molecules to flow smoothly over the airfoil in an ideal manner. compressibility, mass of air molecules, momentum, and friction all work against efficiency. It would be my guess that aircraft engineers stay a fair percentage (25% ???) away from the speed of sound (at any condition) The parts of the propeller that reach this plateau would not be worth the added weight, stress, or other costs. Clearly the point is well taken, the faster the tip speed, the more noise is generated. You don't need to go to supersonic speeds to generate a lot of noise. A whistle or horn intentionally makes a lot of noise with very little air speed. Mooneys are not quiet beasts on take-off and neither are Bonanza's. Our European brothers are seeing new propeller designs that achieve quiet operation and still strive for good pull through the flight regimes. Question for N601X, On the Jabiru is that direct drive? Often, a high rpm engine, rotax and auto engines included, a gear box (or belt) will be used to bring the prop speed back down into the 2,700 rpm range. a 64" prop spinning at 3,300 rpm gives a 514 mph tip speed (using maropers method above) prop circumference = Pi X D = tip distance traveled per revolution. Still 30+% short of the speed of sound at any altitude or temperature. Respectfully submitted -a-

Quote: GeorgePerry BJ, No ego involved here...I'm just passing along what the POH says to do - nothing more nothing less.

Quote: N601RX http://www.mooneyspace.com/index.cfm?mainaction=posts&forumid=1&threadid=372

Quote: N6719N I used to fly a Piper Archer that had factory AC. The way it worked was an outside unit that hung down when you turned it on for cooling. When you were on the ground and needed it most, it didn't get enough air flow to make it work. In flight, it worked fairly well, but that is where you needed it least, especially once you were up to any altitude. As you might imagine, it worked the best at altitude during cruise when you didn't need it at all. Flying low altitude on a hot day, it really didn't do enough to be worth it. On the surface, it sounded like a great idea, made for great marketing from the manufacturers, but it just wasn't that great. And the weight penalty, not to mention the drag on the aircraft was horrible. What a waste...IMHO. Now, AC on a cabin class turbine aircraft, now that is a different matter. Works great on the ground or in the air. I will never opt for AC on a light aircraft with recips. Just my 2 cents worth.

Has anyone considered the posibility that these rumors of Chinese buyers is just a bunch of mis-information to try to encourage US investors?? (if you don't help us out, the Chinese will take us over! Ooh noooes!!!)

What do you think is the threshold at which A/C might be worth the loss in cruise speed and payload?? Lets assume that you're in a turbocharged Mooney and you'll cruise at an altitude where the ambient temp is much cooler. In order to justify A/C in a plane, would you have to spend most of your time at lower altitudes or if you lived in the desert somewhere, or is it's worth shown at busy airports where you might have to spend a fair amount of time on a hot tarmac??

Quote: GeorgePerry I understand that aircraft engines are not "prone" to it, but I've seen plenty of high end auto's that have been driven through water too fast, sucked in some, and the bottom end came out in a violent fashion. The chances of an aircraft engine doing this is slim but it only takes a couple of ounces of water in a combustion chamber to ruin an engine. All I'm saying it that I wouldn't chance it. Bottom Line, visible moisture = closed ram air door

Quote: GeorgePerry It makes me sad to see the chinese swoop in and buy American companies that have been doing business here for decades. It's a sign of the times I suppose but tragic none-the-less.

Quote: flight2000 Guys (and gals), please remember that we lost rgaines back in July of this year. This is an older thread, so keep that in mind. He passed away about a month after he completed all of the mods he was talking about back in 09. Brian

Quote: danb35 All Mooneys, except for the original M20 and the M22, have at least one letter (the Acclaim is the only one I know of to have two letters, the TN). Most, but not all, have a name as well; for some of those, the "name" is a number. The J is also known as (depending on when it was made, and what options were installed) the 201, the 205, the Advanced Trainer, and probably other things I've forgotten. When Rocket Engineering bolts an IO-550 onto it, it becomes the Missile. The K, from the factory, was either the 231, 252, or the Encore (most notable differences between these models are the engines--all are TSIO-360s, but the 231 was either a -GB or -LB, the 252 was a -MB, and the Encore was a -SB). When ModWorks bolts the engine from a 252 onto a 231, it becomes a 262. When Rocket Engineering bolts a TSIO-520 onto any of the K models, it becomes a Rocket (though I've never heard of a Rocket conversion being done on an Encore, and I understand they're pretty rare on 252s). Missile, Rocket, and 262 are aftermarket names, not "official" Mooney designations.

Quote: Mitch My wife is a pilot and Mooney owner! Nothing left to say except, life is good!

Has anyone tried finishing their yoke shafts with gun blueing??

Quote: carusoam Astro, I think you might find that copilot brakes were an option. Often found on MSE versions (M20R MSE at least). -a-

Nawh, it's a Badger!!

Quote: maropers I don't see where that compensates for altitude though. Temperature is a minor variable compared to elevation.

Quote: Immelman I don't see where that compensates for altitude though. Temperature is a minor variable compared to elevation.

Quote: Immelman The speed of sound in the atmosphere varies inversely with temperature. From Dr. Ed Williams' avaiation formulary: Mach Number (M) = TAS/CS CS = sound speed= 38.967854*sqrt(T+273.15) where T is the OAT in celsius. TAS is true airspeed in knots.

I was under the impression that the J was a 201 Missle and the K was a 305 Rocket and Bravo was a 351 Rocket.

Quote: GeorgePerry I wish I weren't a humble government servant and could afford an "R".

Now, I've been told that the reason that direct drive engines operate at a max of 2700 rpm has something to do with the prop tips approaching the speed of sound. Now if you take the speed of sound at sea level and figure for a prop tip speed of .9 mach on a 72" prop, you get an RPM of 3193. Obviously, the speed of sound is much lower @ 30,000 ft, and you can probably push the prop tips to .95 mach. Does anyone have a chart of the speed of sound at different altitudes?? Is there a reason the industry settled on the 2700 figure??