"Larry Dighera" wrote in message
...
On Sun, 28 Mar 2004 11:43:04 -0800, "C J Campbell"
wrote in Message-Id:
:

Do you have such a technological solution?

Noise limits on aircraft in Europe have shown that noise
reduction is not only possible, but it can be a way of life.

http://www.hliese.de/International/international.html

The unfortunate thing is that if you import an aircraft fitted
with one of these into the UK, you have to remove it as it's
not approved by the CAA. Such is life. They have a UK
dealer though! :-) Maybe some are getting approvals now.

How much will it cost?

Ummm... Less than a law suit?

http://www.hliese.de/Preis-02/preis-02.htm

Given the fact that most aerobatic aircraft are equipped with constant
speed propellers, it would be interesting to note the reduction
propeller noise generation during aerobatic maneuvers with the prop
control less than firewalled.

My POH states that aerobatics should be performed with the
prop set to 2600 rpm. Red-line is 2700. It's a CS prop.

Perhaps there are simple, inexpensive,
compromise solutions that could be adopted without significant impact
on performance.

Spreading out the area used over a wider area so people
under a practise area aren't affected all the time?

The police helicopters nightly patrolling overhead in the '70s were so
loud that they woke the slumber of those who they purported to
protect. Now they are so silent, that they are no longer an issue.

Well, they can still keep me awake! I've had a police helicopter
hover near my house a few times looking for criminals in the playing
fields opposite. It's a bit annoying when you're trying to watch TV.
I don't mind so much as I'd rather they catch the criminals. Last time
I just switched the TV off and turned my scanner on, scanning between
the police frequency and the local airport frequency.

How would raising the aerobatic box to a higher
altitude impact its use?

You'd be in the clouds?

Paul