Sunday 10 June

the nimbo trailer nears completion…

meanwhile Liz reports:-

 

“Well, it was a slow start in the murk – but then a nice soaring day today. Congrats to Bob for being passed to fly his lovely new LS4 (after successfully wrestling it back from the CFI!). Trial lessoner John stayed all day and had a great time; Soton Uni’s Tim and George worked on their soaring skills and Tim managed his first mini-cross-country flight; and finally big congrats to Tony P who soared away for his 1000th launch. Thanks from me, Liz, DI for the day, to all who helped make it another great fun day at the club.”

 

https://www.facebook.com/shalbournegliding/videos/vb.128209893925586/1817651711648054/?type=2&theater&notif_t=page_post_reaction&notif_id=1528666317170961

May Bank Holiday Monday

The weather was rubbish, but we can always rely on Paul and Alan for some entertainment.

Downforce

Even with a trimmer as powerful as that on the Puchacz, ‘Transonic Prentice’ can be relied on for some extra help.

“At transonic speeds, an aircraft can experience a shift rearwards in the center of pressure due to the buildup and movement of shockwaves. This causes a nose-down pitching moment called ‘Mach tuck’. Significant trim force may be needed to maintain equilibrium….”

Good Intention Bad Indentation

Composite structures can put up with remarkable amounts of bending and twisting, but they don’t fair as well when being squeezed or poked. A group of us scratched our heads this morning as to how several dents had appeared in the top leading surfaces of the Vega wings, until it occurred that they corresponded with the position of one’s fingers when pushing the aircraft.

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The apparently hard surface of the wings at this point is in fact only egg shell thick, beneath that is a layer of foam on a thin fibreglass substrate. When Andy opened up the worst damaged area, about 50 mm in diameter, further investigation showed the damage had extended to an area about 150mm in diameter. So this little dent turned out to be almost large enough to be recorded as a major repair.

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So when pushing on the front of the Vega wings please place the palm of your hand on the leading edge and avoid any downward pressure on the wing skin.