B2 Autorev Check

[Max Continuous]

Having a bit of a brain cramp here

How do you perform an auto-rev check on the B2 A-Star on the ground?

ie: jetranger is 28-32% Tq.@100% N2

If some one can help an old guy out it would be greatly appreciated.

At this stage every time I learn something new...something else leaks out and you never know what it is you've forgotten!!

Max

[skullcap]

Personnally I find it hard to get an decent number as crosswinds affect it alot. I usually see 24-26% in summer and up to 28 in winter. Remember on Astar you are only checking the low pitch stop thus a little to high rpm will not bother the autorotation characteristics as long as helicopter is rigged correctly(you know just pull it up if too high RPMS). Too low will kill you.

 

A side note on autorevs, when doing the ng drift check you should keep in mind that the low pitch stop(auto revs)is set correctly prior to doing this as the chart used for doing the ng drift check has the angle of anticipator in it. Thus if collective is not in correct location for low pitch you will have inaccurate anticipator angle and could have a fuel control changed for no reason.

[ame206350]

Having a bit of a brain cramp here

How do you perform an auto-rev check on the B2 A-Star on the ground?

ie: jetranger is 28-32% Tq.@100% N2

If some one can help an old guy out it would be greatly appreciated.

At this stage every time I learn something new...something else leaks out and you never know what it is you've forgotten!!

Max

 

Just take it for a flight instead. Do a power check at the same time as you scope out your autorevs.

[ray]

With the 350B2, 100% flat pitch on the ground, you will see 19-20% torque if the low stop is set correctly.

 

To confirm the actual rpm, the graph is in the Flight Manual in the 'Complementary Flight Manual' section in the back.

[skullcap]

This is actually a good rule of thumb to live by. Have had two astars which have failed autorev check and knew so before flight. One the torque was so high that I wouldn't fly even for test flight as if the engine had quit it would have been a smoking hole. Another the sleeves were changed and pitchlinks not adjusted to accomodate thicker size and would not autorotate. Good to know these numbers prior to flight. Although would not agree that 19 % is ok, though as mentioned it is something of a guess, 19 % Q would not kill you though, 34% Q showing is probably not worth the flight. Follow the fm to set up rpms correctly from section 8 and live by the book.

 

Keep in mind all subsequent checks in maintenance manual assume you have a correctly rigged and low pitch adjusted aircraft.

 

sc

[smoothair]

I agree that there may me a rough % to look at on the ground. but. wouldn't that vary even between aircraft. Not all aircraft are set to the same NR at Max continuious. some may be at the top end of the range and some at the lower to give a smoother flight. therefore the NR on the ground would be different. that would make the TQ different per aircraft. A flight and use the FM is the only way to get it right.

[ame206350]

I agree that there may me a rough % to look at on the ground. but. wouldn't that vary even between aircraft. Not all aircraft are set to the same NR at Max continuious. some may be at the top end of the range and some at the lower to give a smoother flight. therefore the NR on the ground would be different. that would make the TQ different per aircraft. A flight and use the FM is the only way to get it right.

 

Agreed. Test your autorevs in a situation that best simulates where you'd be when you actually needed it. In the air. Not sure why anyone would bother with being too lazy to do it the right way.

[Hazy]

"Agreed. Test your autorevs in a situation that best simulates where you'd be when you actually needed it. In the air. Not sure why anyone would bother with being too lazy to do it the right way." -ame206350

 

The right response from a QA guy. Hazeus

[Max Continuous]

Agreed. Test your autorevs in a situation that best simulates where you'd be when you actually needed it. In the air. Not sure why anyone would bother with being too lazy to do it the right way.

It's not a question of being lazy, I was looking for a "rule of thumb" before commencing flight and the actual test.

Thanks so much for your insight, name calling is always helpful.

Max

[ame206350]

It's not a question of being lazy, I was looking for a "rule of thumb" before commencing flight and the actual test.

Thanks so much for your insight, name calling is always helpful.

Max

 

I wasn't calling you any names. Take it easy. I was simply recommending that an actual in flight auto revs check was the better option as far as accuracy goes.