Images of TST Tailplane Failure

[Guest TOSGcentral]

Images courtesy of Jim Christison. Many thanks Jim.

 

 

 

 

Jim also added the point that it was the port side that failed first. This is something that I overlooked. The Thruster tail units are symmetrical and can go on either way but are usually dictated by the way you put the skin on so the Velcro flap is underneath and out of sight.

 

If you are checking your aircraft for this fault then it is the thinner male side that you need to examine irrespective of if it is on the port or starb side of your aircraft.

 

I have quite a few tail units laying around at the moment so will add another general image of the two halves together once I have enough light in the workshop.

 

Aye

 

Tony

 

 

[Guest TOSGcentral]

New Images of Failure Site

 

David Hill yesterday produced some excellent close up images of the failure.

 

With David's kind consent you may view these on his web site at:

 

http://www.davidsusan.com/pict.html

 

Many Thanks David

 

T.

 

 

[Guest TOSGcentral]

'Exploded View of Tail Unit to Assist Inspection

 

This is an ‘exploded’ view of a Thuster chromealloy tail unit (horizontal surfaces only).

 

The image is a composite of components from T300, T500 and the T100 Prototype parts as all have identical root fittings. Bushes are not shown.

 

(Click on thumbnail to enlarge).

 

 

To understand what you are looking at:

 

• Top centre is the detached elevator drive bellcrank and shaft. This normally lives in the rearmost large hole on the boom and is fixed in position – it stays there when you de-rig the aircraft.
   
   
  
• To either side are the elevators (T300/T500). One has the skin off so that you may see the structure. The other is fitted with tail unit formers. These formers may well have given Robin a bit more elevator authority and assisted him in his most challenging task. The elevators are firmly bolted to the transverse drive shaft and locked to the tailplane by fixed outer hinge pins (plus Velcro gap sealed to the tailplane)
   
   
  
• To the left is a T300/T500 tailplane half. The tailplane rear spar fitting plugs into a bush in the other large hole in the boom each side at the rear.
   
   
  
• To the right is one half of the T100 tailplane. Do not be put off by the larger Mean Aerodynamic Chord in comparison with the standard as the root fittings are identical to the others. What is of interest is that the T100 had double bracing at the leading edge as well as the trailing edge. The Swift Prototypes that I am currently building will also have the same double bracing as part of the 450kg MTOW mod that is being certified.
   
   
  
• The failure section that you need to look at is the tube on the white pad left of centre.
   
   
  
• The long tube section could be either side on your aircraft as the tailplanes are symmetrical and can be put on either side depending on how you have fitted your tail skins to keep the Velcro union underneath and out of sight.
   
  

 

 

I trust this clarifies the area that you need to examine.

 

Aye

 

Tony