Hoffmann prop

Abstract:    Firstly the uneven pressure on the thrust plate will cause breakage of one of the four through bolts.

Subject: Hoffmann prop.
From: "John" johncallahan@yahoo.com
Date: 9/8/08 5:53 PM
To: Taifun17E@yahoogroups.com

Hi Fred, there are two consequences relating to your propeller problem. Firstly the uneven pressure on the thrust plate will cause breakage of one of the four through bolts. The latest modification, "revision P", replaces these 8mm bolts with 10mm bolts because of breakages that have occured on aircraft with both thrust bearings in place. You will find that this mod will be mandatory at the next propeller service, max six years TBO. The second effect of the uneven pressure is crankshaft damage due to radial load. It is very important that these bearing contact the thrust plate at the same time.

There's no place like cloud base.
John.

Subject: RE: [Taifun17E] Hoffmann prop.
From:"Fred Bonar" fbonar@yahoo.com
Date: 9/9/08 7:32 AM
To:<Taifun17E@yahoogroups.com>, "'john neel'" vortecx@yahoo.com, "'Jim Bagley'" jbagley@yahoo.com

Thanks,

Know where to find the rollers and “revision P”

Subject: AW: [Taifun17E] Hoffmann prop.
From: "KORFF LUFTFAHRT DB" cornelia.korff@yahoo.com
Date: 9/9/08 12:41 PM
To:<Taifun17E@yahoogroups.com>

Modification „P“ will be done by the manufacturer HOFFMANN during next overhaul, no need to do this now.

This modification was created by HOFFMANN because of vibration problems with H36 Dimona motorglider with Limbach L2400EB1.AC or SAUER S2100 engines. Modification “N” is a little hard to change pitch from take-off to cruise. Sometimes you feel like pulling against a solid stone during pitch change! The trick is to reduce RPM to about 1800 – 1900 RPM for pitch change from take-off to cruise position. This will help to prevent the bearings and the pull plate from damage.

Best Regards,

Cornelia Korff

(Technischer Leiter)

KORFF LUFTFAHRT

RAINER KORFF

Flugplatz Mainbullau 7

63897 Miltenberg

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Tel. : +49 9371 99145

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