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Dragonmount

Overspeed question

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I've recently run into trouble where right after takeoff my aircraft goes into overspeed and it counts as a crash. My question is, shouldn't I have a second or two to fix the problem before the plane flies apart?

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Depends on the plane. Some crash very shortly after VMO. Just set 'ignore crashes' in the Realism tab, its more annoying a feature than useful.

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I agree with VB, that can be a real pain in the ...!

On a second thought, how is it possible to get an overspeed right after takeoff? I mean, if I pull up the nose of any aircraft to 5-10 degrees this will definitely reduce my speed, or at least slow down the rate of acceleration, so you have time to retract the flaps (They might be the cause of the crash - did you check the maximum speeds allowed at your flaps settings?) and reduce power.

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I'm learning to fly the Carenado PA46T, and the problem always seems to happen just after i retract my flaps, should I lower my speed before retracting flaps?

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Real world wise, most planes won't fall apart if you exceed VMO. Every now and then you will get the overspeed warning when you get a gust or a temperature change when flying close to VMO. In the DC10 we called it chicken clucker minus one speed. The big thing is no to overspeed flaps and gear. This could lead to damage and frozen position as you bend metal. On acceptance flights, we also test the overspeed systems by intentionally exceeding VMO to ensure the warning activates at the proper time. There is a safety margin factored in on most speeds.

 

Just keep in mind the up/downhill effect and drag. If you retract the flaps, the aircraft will speed up. Reminds me of flying the G3 years ago. As soon as the gear handle light extinguished on retraction, you pulled some power. This measure protected against over speeding the flaps. Once the gear was up, the jet speed up quickly with takeoff power set. Also remember as you lower the nose to level off, you should also be pulling power. Once you get used to flying aircraft, you will have a good idea to how much to pull or add. Just practice descents and climbs until you can maintain your speed throughout the maneuver.

 

In heavies, we retracted the flaps on schedule after reaching accel height and setting climb power. Just remember to pull some power when ready to clean up.

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Dragonmount,

 

There must be more to it than this.  If you're flying the Jetprop, you should be lifting off around 90 with half flaps, and the airplane simply won't accelerate that fast.  If everything else with your software and hardware is correct, you'll have plenty of time to get the flaps up.  The Jetprop isn't going to exceed Vmo in a moderate climb. 

 

Perhaps you're overspeeding the engine.  Set the takeoff torque between 1100 and 1150.

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I'm learning to fly the Carenado PA46T, and the problem always seems to happen just after i retract my flaps, should I lower my speed before retracting flaps?

 

The JetProp is a bit special since it's a piston Malibu that has been converted to turbine. The engine is much more powerful than on the stock airplane, so airspeed will increase much quicker. After take off, your pitch angle will be much higher than with most aircraft and you'll climb at ~3000 fpm. Also, with the turbine, you'll never take off at full power, since this will likely over-torque the engine (see the documentation for max values).

 

Also, during conversion, the airspeed indicator loses its "yellow arc" and the redline is moved back from top of the yellow arc to top of green, ie. reduced from ~200 kts to ~170 kts. From what I've read, this was a requirement to get it certified (same thing was done with the Turbine Duke conversion). It doesn't mean the plane will explode at 174 kts. In fact, I read that some JetProp pilots still fly their planes at 200 KIAS, though that would of course be illegal.

 

I always fly with crash and stress damage turned off. I got sick of crashing into invisible objects or having the plane disintegrate in mid-air for no apparent reason. If you want realistic damage modelling, there are some add-ons that give you that.

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