Graham,
For the first time your explanation doesn't seem very clear to me. I thought
today there would be a more scientific approach when making a propeller and
its application. If the Warp blade is so few adequate for the Europa and
Arplast so good then why don't we have the choice since Airmaster is not the
manufacturer of the blades?
Best regards,
Karel Vranken.
----- Original Message -----
From: "Graham Singleton" <grahamsingleton@btinternet.com>
Sent: Monday, May 28, 2007 11:47 AM
Subject: Re: Europa-List: re:propeller optimization
> <grahamsingleton@btinternet.com>
>
> Fred,William Ira
> William and everyone
> I continue to be puzzled by the Warp Drive prop, which we all know was
> designed for slow microlight A/C. Jerry Davis once pointed out that you
> need less twist at hi speed, which can only mean that the Warp has the
> wrong twist at any speed! (Jerry is UK agent for Arplast)
> Thinking for a moment, at the root the blade angle should be nearly
> parallel with the direction of flight. At the tip it will be dependant on
> speed, diameter and rpm, (of the prop) With a VP prop it will only be
> optimised at one particular speed but should be a good compromise for the
> speed range.
> I haven't done any sums so more than that I won't say at this point.
> Graham
>
> William Mills wrote:
>> <william@wrmills.plus.com>
> the latest Arplast blades PV55 have a slim aerofoil with plenty of twist
> (hub to tip) to cope with cruise
>> speeds of 120 /130 Kts (about 24 degs is required) Regards,
>> William
>>
>
>
>
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