Slingsby T53
 

Hi chaps-whilst googling a few of my childhood memories I came upon this forum and this thread. My father designed the T 53 and as he has pulled the plug on the internet, having better things to do with his time he suggested I could join on his behalf. I have printed & posted this thread to him in Scarborough and will post his comments in due course

T53
 

As a replacement for the fretwork fighters it was not that bad it was just the jump from "chisels and glue" to rivets that seemed to be the problem at Kirby Moorside.
Should have replaced the T21 to start with.
Pobjoy
(people forget how many "lost flying days" there were with the barges due to wind)

Spoke to dad last night and he described the Blanik as more sophisticated in design, and he does recall getting stuck inside the fuselage of one after having crawled inside it with a tape measure!!!! Suffered a panic attack and had to be dragged out by his ankles.!!!
The reason for the parallel chord wing was to use one universal rib with pressed flanges and the rivet holes in the flange were the datum so that the ribs were the same in both wings
Financial problems were a big issue at Slingsbys after the death of Major Shaw, the original chairman and shares were sold to pay death duties.

roys,

Welcome to PPRuNe. I am sure there are lots of regulars here besides me, who would be very interested in hearing more from your dad about the T53.

T53
 

It was quite obvious that the T53 was designed "down" to a budget as opposed to the Blanik being a state subsidised product.
However the T 53 was really supposed to be a "basic trainer" rather than a "soaring" machine and therefore its "simple" design would have been quite adequate for its (up round and down purpose)
As touched on before the main improvement would have been its actual ability to be used on many more days than the T21 (without having to festoon it with people hanging on to it).
When you add on the benefit of not having to dress up like a first world war balloon observer in the winter it got my vote.
I also think it would have "upped" the standards for the operation and perhaps given cadets more of an incentive to continue with civvy club flying after going solo.
I flew it as a staff cadet with no prior experience of a modern day machine and could only see it as an improvement on the existing aircraft with no adverse "handling" issues that made it less fun or more difficult.
Air brake and aileron "tweaks" would have come through as required and less people would have left the system.

Slingsby T53
 

Spoke with dad this evening and he has promised me a letter in reply to the criticism on here.
Wooden sailplanes had been axed by Slingsbys due to rising labour rates and new standards of accuracy demanded by low drag wing sections.
To set the scene,the T53 was designed over the winter of 1966/67-the year of my birth, so perhaps its my fault for all those sleepless nights! Knowing dad he probably stopped at work to avoid all that domestic stuff!
He joined the Sigma project as of January 1967.
On the morning of the first flight of prototype he had just arrived back from Germany meeting F X Wortmann,regarding the Sigma project, to be told it was going up.
After ceasing to do Slingsby work, a replacement designer was engaged to be then followed by Pat Monk and I found an interesting obituary here
Pat Monk - RIP - Key Publishing Ltd Aviation Forums
Pat Monk was a most capable chap and also built a house extension during his time at Kirkbymoorside!
I also found an interesting article on the next saga ,the HP14 here
http://www.soaridaho.com/Schreder/HP...4c/Hp14V_C.htm
and this mentions Joe Provins workshop in Scarborough, which I visited with Dad as a young child and still have a memory of it now. It was a 1st floor workshop on Silver Street Scarborough and the building is still there.

Joe Provins had a car body repair business, was not impressed by the Hp14 and died in his forties one day after flying the Hp14, of jaundice.
To complete the morbid theme of this posting my father decided if Geoff Bailey Woods did not survive the test flying of the prototype T53, as they both had young families, my father would gas himself in the oven at home!
This might seem extreme but he had sadly seen a lot of death on the Buccaneer test flying development team at Holme on Spalding Moor.
If any of you chaps know of a current location of either a T53 or Torva sailplane in the UK which I could view I would be most interested.

T53 first flight 3rd April 1967
 

http://i854.photobucket.com/albums/a...irstflight.jpg
Left to right Fred Slingsby, Derek Piggott and my father J L Sellars.
Was also my fathers 30th birthday!

T53
 

The last one i saw was hiding at Dunkeswell many moons ago (civvy version) derigged.

Lovely photo Roy...got any more interesting pics in the family album ??
Just as a matter of general interest do you have access to any of the original Flight Test reports by Derek P /other test pilots ?

rgds baz

More family history
 

2 albums of gliding stuff and 1 of vintage motorcycles from that period!
However this is the T53 thread so I will just treat you to one more.
http://i854.photobucket.com/albums/a...tled1-Copy.jpg
Not much aeronautical about it-but if you compare it with this
http://www.flightglobal.com/pdfarchi...e of edinburgh
It is the picture from the photographer in the right hand corner-which I find quite unusual and it is interesting to see the slight movement of the subjects of the picture.
Reading the caption of this picture also indicates the ridiculous workload of the small factory,which was five types of glider and two types of aircraft.

Here is the Flight International report:

If it is written by the Michael Wilson I think it is, I'll email him and ask if he has any more recollections of it.

Just a guess but I wonder if all those ribs were to stop over enthusiatic cadets denting the wing when pushing it back to the launch point?

That 'Flight' link was posted in post 16,what I was after was any of Derek Piggots flight test reports (or any other test pilots report) for the T53.
Might be interesting reading.
Dont know about the wing design criteria - perhaps Roy could ascertain that for us ??

Derek Piggott is still around albeit aged 87 now. He was very helpful with flight test and tuning information for my own glider, but I would be loath to approach him to research the T53 without an actual need for the info.

Here's a bit more on a T53 survivor in the Isle of Man:

Andreas Gliding Club

There was also A 72" span model of it published in Radio Control Models and Electronics in about 1972. It was that article which made me wonder why I never saw any.

Slingsby T53 design
 

A couple of years ago Dad gave me some old Flight Internationals. One had that flight test report in and another one an issue or 2 later with a picture of Concorde on the front. Could not understand as to why he had got it until I came to the letters page. One very angry letter allegedly signed by my mum complaining about the omission of my fathers name from the article!

Slingsby T53 design
 

Answers to various questions I have put to Dad on the T53 have been answered thus:
"calculations could have been done on flight handling and structure but were not deemed necessary-what had worked for them in the past was used.Air Ministry data was used ,for rib spacing calculations could have been done on skin buckling but were not."
He then told me what happened after he left and a weight saving redesign was done but I do not intend to put it on the internet!
Dads design for the spar, which was laminated and bolted was based on his previous job at a firm of structural steelworkers and was done for cheap manufacturing but was redesigned by Pat Monk using machined components and put up the cost considerably.
I presume "Air Ministry data" was some kind of design bible.

Watts my Line by David Dixon Redline Books 2006ish
 

Dad gave me this for last years Xmas present and told me it was worth reading for the incredible errors in it! Leaving aside 16m Darts and the 18m T53, the author states that it was an all American design!
Dad never met this chap Lawrie Watts and presumes he was got in to do some cutaways of the Dart/T53/Hp14.
The drawings in the book are very nice though including one of the retracting undercarriage on the Dart, which was one of Dads first jobs at Slingsbys.
I have emailed the publisher of this book who informs me that accuracy is important to them and IF the book is reprinted it will be corrected.

Andreas Gliding Club
 

Thanks for the link-I have printed & posted it to dad & mentioned about flight test reports.See if it jogs any memories!

I was with 611VGS at RAF Swanton Morley. The T53 was brought to Swanton Morley, which was also the home of No.1 Gliding Centre, and our OC Ron Page had the opportunity to fly it. He was told he could do what he liked with it so he pulled a couple of loops which pinged several panels in the wing. We never saw it again.

hi Roys

did your dad design the early hydraulic retracting Dart u/c (resulting in PIOs on aerotow as one pumped the hndle) or the replacement, rather cruder but effective mechanical one?

And what is his version of how Fred named the Swallow?

(Sorry for thread drift).

Slingsby T53/Dart
 

Derek Piggott had a bit of an experience after pulling a loop at the Farnborough Airshow demo but it was kept quiet. This was after the first weight saving redesign by Mr Slater, dad had joined Sigma prior to the first flight as previously mentioned.
Interesting comment about which Dart u/c it was, as in my notes dad had used the word replacement which I did not use in my earlier post.
Do not know about the Swallow name but will ask next time I ring.
Any more questions from that period please ask and I will mention them