Obviously it'll never fly again, but what is the ultimate goal with this one?
Nope, no flying for this one any time soon. Many moons ago we wanted some valves from it to rebuild Bluebird's
onboard start system. Much research and pleading with Goodrich Power Systems for the use of the old Lucas Rotax archive revealed that our start system had evolved into that on the Vulcan and many parts were compatible so if we could raid the old Vulcan we had spares for Bluebird
But the engine bay doors don't open, we were told. Of course they open, we replied, they're doors so if we can get them open can we have the valves? So we opened them for the first time since the RAF had closed them up in 1983 to find that the engines were pretty well bricked up in there out of the weather and were, outwardly at least, in good order. They didn't seem too bad inside either so we suggested there and then that one day we'd come back and see if we could get one going.
At that time, however, we didn't have the know how or the contacts so it remained pie in the sky.
But fast forward to 2019 and suddenly the Bluebird
job is having an unexpected hiatus so we thought we'd go have another look only this time all we saw was a very big Orpheus and lots of familiar valves and pumps and stuff we understood.
So, as to the goal, at the moment it remains to start one engine (No. 4) and do a spot of paintwork because she's looking grubby. I don't quite get the whole Vulcan thing - to me it's just a big test stand for the engine we're working on but many folks are quite smitten with it so if getting an engine running adds to the romance then so much to the good. Where we end up depends on the Bluebird
job coming back on line because that's obviously our priority and our first love but there's another three Oly's hanging from the test stand so we're not short of things to amuse ourselves with.
While we're on-topic, we plan to have a working day on the aircraft at the end of the month (weather permitting, of course) to paint and clean and generally prettify her grubby exterior. Or friend Feo is looking after recruitment so keep an eye if you'd like to come along and get scruffy and have a laugh with the crew.
As for O-rings... the old Nitrile rings that keep the fuel inside the fuel system are manufactured with a plasticiser in the material to make them nice and pliable to give a good seal but once exposed to fuel the plasticiser dissolves out. But that's not a problem because the fuel seeps in to take its place so nothing changes and the O-ring keeps doing its thing. That is until it finds itself no longer bathed in fuel at which point it dries out and shrinks and stops being a seal altogether. The question at that point is whether it cracks or not because if that happens it's game over.
Our first step with bringing our fuel system back from the dead was to get the HP spool in the engine turning because that's what drives the pumps, but that's another story.
Next we pumped 10 litres of WD40 straight into the inhibiting tapping on the fuel system, which is quite high on the engine so it soon appeared at the pump bleeds and crept around in there for a couple of days doing what WD40 does. The problem with WD40 is that it flashes off fairly quickly and the second problem is that it was falling back out again at quite a rate from a joint where the rotary throttle meets the rest of the fuel system and that was what's known in aerospace speak as - bad!
With the inside of the fuel system steeped for a couple of days we then followed it with diesel, filling it from bottom to top and performing a couple of wet cranks to be sure that fuel was being metered all the way to the burners. It was and it poured in torrents from the combustion chamber drains, but also from the joint with the rotary throttle. We'd not dare try to start it like that, there'd be jetfuel everywhere, so we had a go at taking it apart. That didn't work as easily as it would appear when looking at the outside so we sent for the drawings (don't ask) and that proved we weren't getting it apart any time soon. So we called the very top O-ringologist in the whole of aerospace for a diagnosis and were told how it all works and that it might come back or it might be cracked.
On Saturday we filled the system again and, sure enough, out it came in a steady trickle so we kept topping it up while we did battle with a boost pump in the wing. And then, as though by magic, the trickle slowed to a few drips here and there that slowed to a single drip from one point to no drips at all. It just stopped before our very eyes. In went more diesel but it wasn't coming out anywhere with the result that yours truly got properly hosed with the stuff when making the disconnect later on because by now it was pressurised in there but that was a small price to pay.
We'll fill the other engine fuel systems with diesel because we can. It will certainly do them more good than harm and you never know, one day we might start some of the others.