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Aerobatics ServerACRO E-mail Archive Thread: [Acro] Re: MT Prop AD / Wide-chord blades[International Aerobatic Club] [Articles etc] [Communications] [Contest and Patch Information] [Aviation Organizations] [Other Aerobatics Info] [Aerobatics Images] [Other Aerobatics Links] [Other Aviation Info (including weather)] [Search ACRO Website]Disclaimer: These aerobatics pages are developed by individual IAC members and do not represent official IAC policy or opinion. |
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Thread: [Acro] Re: MT Prop AD / Wide-chord blades
Message: [Acro] Re: MT Prop AD / Wide-chord blades
Follow-Up To: ACRO Email list (for List Members only)
From: Eddie Edwards <eddie at tates.com.au>
Date: Thu, 19 Dec 2002 11:31:49 UTC
Richard The wide blade prop makes sense as we found the same on our R/C models ( international aerobatic competitor )- The blades can operate at lower angle of attack and thus are more efficient - less drag etc. Larger diameter produces more thrust at low airspeeds but there is a limit to overall improvement , as well as ground clearance and straight line speed will be slower - can be acceptable but speed is still needed for entries to verticals where energy is important to get good vertical penetration. All that's needed now is to go to a scimitar style blade profile and or- better tip design - try an angled tip shape- reduces noise and improves blade efficiency - less tip drag - as the very tip is all drag and is only there to make the inner part of the blade work. My experience is only from 20 years of testing and making propellers for my models - I had a bit of a fetish for props as my old prop box will attest to ! Currently fly advanced in my YAK 55 - 400 hp and 260 MT prop. In Australia. Cheers Eddie Edwards Richard Goode wrote: > Dear Acro > > MT Prop AD / Wide-chord blades > > * Some MT customers are under the impression that there is a new > AD affecting MT propellers. This is not actually the case and > what has been issued, is effectively an extension of the earlier > one. The facts are as follows: > > * There was an earlier AD for the lagg screws for MTV3 and MTV9 > propellers, which involved taking out the blades and checking > the bolts at each blade root. > * This was only applicable to propellers manufactured up to and > including 1999. Subsequent propellers are not effected. However > the FAA expressed a concern that a propeller might be rebuilt > with a later hub (hubs are identified by a serial number > beginning with the two digits of the year of manufacturer (ie > 99/00 etc) into which earlier blades (ie pre 1999) and therefore > to be checked for AD compliance could be inserted into the later > hub. This could cause someone checking for AD compliance to be > satisfied that since the hub was made after 1999 this would also > apply to the blades. > * Effectively therefore nothing has changed - only blades made > before and including 1999 should be checked - but the assumption > is that all affected blades have already been checked! > > The following will be of interest to owners of Sukhois and Yaks: > > * For the new Vedeneyev M14R (450hp) engine, Vedeneyev designed a > new propeller, since the existing MTV9 - 260 (102" diameter) > blade would not be able to transmit the power. > * We did not want an increase in diameter beyond 2.6 meters, which > with most Sukhois would begin to create a ground clearance > problem, and the solution has been a new wide-chord blade, but > retaining the 2.6-meter diameter. > * The first production propeller has now been tested on a "back to > back" basis on a Sukhoi Su-31, but using the same 400hp for both > tests. I am pleased to say that the performance increase has > been quite spectacular - the 15mph increase in top speed; and > between 6 and 12% improvement in terms of vertical penetration, > depending on speed of entry. > * This propeller will be made in both 250cm (98.5 inch) and 260cm > (103 inch) diameters. > > If anyone wants any more information please contact us as below. > > Richard Goode Aerobatics > Newport House > Almeley > Hereford > HR3 6LL > > Tel: +44 (0) 1544 322200 > Fax:+44 (0) 1544 322208 > www.russianaeros.com <http://www.russianaeros.com> > > > ---------------------------------------------- > This message has been scanned for viruses and > dangerous content by the http://www.anti84787.com > <http://www.anti84787.com/> MailScanner, and is > believed to be clean. -- Best Regards Eddie Edwards Tates Toy Kingdom / Tates Performance Hobbies Toy and Hobby Retail, Importers & Wholesalers 135 Shannon Ave Geelong West VIC 3218 Australia E Mail : eddie at tates.com.au or eddiee at primus.com.au Web : www.tates.com.au Phone : Bus. 03 52224201 Intl. 61 352 224201 Mob. 0438 521576 Fax : 03 52231257 Itnl. 61 352 231257 Attachement 1: part2.html
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