Turbines, Turbofans, Turboprops, oh my!

[Saab 2000 Pilot]

You would think so, but the standard version doesn't have drop down masks for pax, so it can only go to FL250, or right in the tops. Even if you pay for the drop downs, it can only go to FL270 for some reason. It'll get there in a hurry, however.

Nope ! Wrong ! The Saab 2000 is equiped with passenger O2 drop down masks and certified for FL310. We used to fly up to FL310 all the time, but lately due to RSVM we can only go up to FL280 in Europe. I heard that they are working on a modification package, but in today´s market....who knows when and if it will be installed

You are right though when you say that it´ll get you there in a hurry. Cruise speed, even @ FL 280 : Mach 0,62 !

 

[Brett Hull]

Didnt the Convair 990 have a fan on the aft turbine?

Not too sure about the 990, but the CF-700 on Falcon 20's do. It's basically a CJ-610 with an aft fan that's pretty much just along for the ride...or so I hear.

 

[Long Time Gone]

Eriknorth-

How's the training going? Is she beating you up really bad? Peachtree seems like a nice place to be...

That "she" wouldn't happen to be named "Jenny H...", would she?

 

[EagleRJ]

That's the one.

The TV commercials made the thing sound like the wave of the future. Wonder what it sounded like?

I saw a video of the prop-fan testbed a few years back, and it showed several passes by the camera, including one where the JT8-D was throttled back and just the prop-fan was pushing. The thing made this obnoxious droning sound that probably wouldn't have gone over very well with either passengers or airport neighbors.

I don't know what they were thinking with the design. The engine core remained the same, so I don't know where they expected to gain fuel economy. The blade tips must have been deep transsonic, so I wonder how they could have been more efficient than a conventional fan?

 

[alohadmac]

Propeller has been the way to go for decades after the Wright Brothers. But propellers limit the forward speed of the aircraft, as the tip of the blades reaches sonic or supersonic speeds, and you don't want that.

So that's why there are no turboprops that streak across the sky at 450 knots.


Archer

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Not bad BUT, the Russian Tupolev TU-95 Bear (4 eng turboProp) can do about 500+ kts in level flight!! Pretty sure it's the fastest prop driven aircraft!

Aloha

 

[stillaboo]

The PT6A-67D installed on the 1900D's generates 1279 SHP, and 1353 ESHP, so that's a grad total of 148 HP of jet thrust, enough to move a 172 or something, at least.

And the new JSF and F-22 both have high bypass turbofans, as far as I know. Both can supercruise too, so I'd say high bypass CAN do supersonic flight. It's not about how fast the aircraft moves, only how fast the air moves through the engine. Can't wait to see a scramjet in action.

-Boo!

 

[ShawnC]

I believe this has been posted on here before:

The NASA Turbine engine simulator.

http://www.grc.nasa.gov/WWW/K-12/airplane/ngnsim.html

 

[EagleRJ]

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Not bad BUT, the Russian Tupolev TU-95 Bear (4 eng turboProp) can do about 500+ kts in level flight!! Pretty sure it's the fastest prop driven aircraft!

Aloha

The TU-95 has engines that develop 15,000 SHP each. I'm pretty sure that's the biggest turboprop that's ever been built. It also has counter-rotating props that go supersonic at the tips, so it's supposedly one of the loudest airplanes in the world- sort of like a C-185 x 200!

Has anyone seen pictures of the new military transport Airbus is going to build? It's going to have four 12,000 SHP turboprops with 8-blade propellers. It won't use counter-rotating props, so the engineers have said they realize that they will have some "torque issues" to deal with. Can't wait to hear it!

 

[A Squared]

so it's supposedly one of the loudest airplanes in the world-

I've heard that honor may go to the XF-84H, A turboprop version of the F-84 ... yeah, that's what I thought.. Whaaatt???? anyway, it's prop tips went 1.18 Mach on a static runup. Apparently the noise was loud enough to knock people out if they were in the wrong place.

 

[avbug]

I'd have a hard time believing that anything could be louder than the PB4Y-2 at takeoff RPM, inside the cockpit.

For kicks one year I took along a db meter, and it pegged it right out. I went into Fresno, and stood by the runway with the meter while two F-16's departed in afterburner. The meter registered 115.

Between the short stacks, props, and the inboard upper collectors, and the ranger V2 apu under the floor, it was not particularly quiet...even ANR headsets couldn't keep up.