Max speed

[peterj]

According to the manual the max speed is 350 km/h at S/L

How come you get an IAS MAX warning at 300 km/h and damage occurs 10-20 km/h above that?

[r-unit]

It depends, yes you will get warning of over-speed, but are you over-tourquing the rotor at the same time?

 

I got it to 340km ish in dive, with overspeed warning but not over-tourquing... so no damage occured.

 

 

:)

[Namenlos Ein]

Take a look at this: http://forums.eagle.ru/showpost.php?p=545617&postcount=1

 

412 km/h!

[V1Rotate]

yes but did he survive the pull up?

[Yo-Yo]

Yes, he did.

 

By the way, he mentioned that rotor rpm value is 82% at low blades pitch but the engine runs at TO power.

 

Pull up must be as gentle as you can.

 

No turbulence of course. Significant turbulence puts restrictions for some maneuvers.

[peterj]

Yeah that was the problem.

I see that if you avoid to over speed the engines by lowering the collective accordingly the aircraft wont break at higher speeds.

[Yo-Yo]

Yeah that was the problem.

I see that if you avoid to over speed the engines by lowering the collective accordingly the aircraft wont break at higher speeds.

 

I can guess that the statement must be inversed: if you avoid to under speed the rotor it wont break. The higher is rotor rpm the lower is flapping, that's the point.

[peterj]

OK, so the engine rpm limit is hit because it's trying to maintain rotor rpm?

 

And a lower rotor rpm means there's a greater force on the rotor blades (in this case) and eventually they'll break?

[Yo-Yo]

1. Yes.

2. No. As you can see the blades travels up and down during one rotor revolution. It permits to avoid rotating moment due to the different velocities of advancing and retreating blades. This movement provides necessary blade AoA difference to compensate it. It is FLAPPING. As the speed increases the flapping increases too.

The centripetal force lowers flapping so if your rpm decreases and the flapping becomes higher you will get blades intersection.