18 July 2011 - Wings 100% complete, tail on, instrument panel in, the “80% done 80% to go” mark passed. The finish line is in sight
On Friday afternoon I (James) flew ZU-TAE, the Airplane Factory demo aircraft, down to Durban for the Virginia Airshow over the weekend. We had 6 Slings on the field and lots of interest from the public.
I was the lucky one, back here at the factory everyone was working non-stop.
What a great feeling to arrive back to see the tail on the fuselage, the wings 100% completed and all buffed up, the engine with all the basic accessories on and the canopy checked for fitment and ready for the final inside layup. That took place overnight and the layup is completed and drying this morning, heated with multiple heaters.
Meanwhile Gareth and Buto commenced wiring the instrument panelat midnight, after having already worked for 17 continuous hours, and right now, at 08h15, they’re still going at it. The result, however, is that the sexy Sling 4 ATW panel is fitted and the lines laid – see below.
Today’s focus is to complete the wiring, to get the fuel lines in and to install the control systems. That completes 80% of the remaining 20%. Then it’s just wings on and finishing. In practice that all takes some time – we need to wait for the Sikaflex glue we use to bond the canopy glass to dry, we need to shape the wing nacelles and finish the shaping of the dorsal fin, trim and fit the cowling and so on. The net effect of that is that the aircraft is likely to fly only on Wednesday afternoon.
Notwithstanding this, we will be “launching” her tomorrow morning, 10h00 Tuesday 19 July, with the Director of Civil Aviation, Mr Gilbert Thwala present to commemorate the occasion. We look forward to showing him around our premises and explaining how we do things.
We’re getting lots of questions about when the Sling 4 will fly and when Mike and Jean will be leaving. Of course everything depends upon safety considerations and there being no hitches. The time it takes to get things done does mean that we seem to be moving the date backwards and backwards. Provided the Sling 4 can arrive in Oshkosh before the end of the show, however, we won’t delay the trip, we’ll go as soon as we’re ready. So departure now looks most likely on Friday afternoon 22 July or Saturday 23 July. Weather permitting the trip can quite easily be done in 6 or 7 days, so that gives Oshkosh on the most exciting and busy days, Friday or Saturday of the show.
More as we go.
Cheers from the team
PS - On the two questions - first, why leave things to the last minute? The answer is that we've been incredibly busy recently with the business generally, having taken 10 orders in May, there're lots and lots of people coming through and it's hard to ever get a complex project to finish on time. Safety absolutely cannot be compromised and everything just seems to take more time than planned. Nevertheless, this is the culmination of 15 months of work, so it's certainly not a last minute effort! It reminds me of the maxim about what do you do if you've got a crisis which will strike in 10 seconds? - You think for 9 seconds and then act. Our fabrication capacity is now good. The thinking and developmental work took loads of time and we're no on short finals with the stuff we know how to do well.
Second - when will be fit in the 40 proving hours? The answer is "I don't know". As things stand we'll be requird to do 40 proving hours. We have asked to be able to do some at night and some on a long'ish ferry flight simulation, as we need to test the aircraft for that, once we've flown perhaps 10 hours and the aircraft is safe. We are going to request a special once-off dispensation to test for 25 hours, however, on the basis that although the aircraft is a new type, the systems are all precisely the same as in the standard Sling, the instrument panel forward is exactly the same as the standard Sling with a 914 engine, of which there are 3 flying, and the aerofoil, tail sections and so on are the same. In practise we'll know 80% of what we need to know within 2 hours and we'll certainly know everything we need to know, at least until full approval testing, within 10 hours. The rest would be just "flying around". Whether we get that, however, remains to be seen.
Flight waiting.jpg
and waiting.jpg
and waiting.jpg
Completed wing - Lyle relieved not to have to paint.jpg
The tail's on.jpg
The beautiful panel and its creators - Gareth, Vince and Buto.jpg
Mike testing an immersion suit for fitment - thanks Chalkie.jpg
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