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Phil Croucher

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Posts posted by Phil Croucher

  1. Hmmm - Single malt - at least I'm not in Ontario where they add corn liquor to it so there is "local content"! Well, they do it with most drinks but I believe the whisky manufacturers told them to rearrange a couple of words into a well-known phrase or saying! ;)

     

    I'm down here opening up a satellite base for my JAA school, now that the oil companies appear to have decided that the JAA/EASA one will be the licence of choice, so I am informed.

     

    Now let me see - Laphraoig today, I think.......

     

    Phil

  2. hey cap - I'm in Spain right now and had to bring my own single malts with me :( Wouldn't mind looking at those movies myself - are they on utube? :)

     

    Inventorguy - good points, and it is true that washout is not perfect, in fact proper washout would be so inefficient that they have to compromise at about 10 degs or so so that we can fly the machine. The end result is that, although washout is an attempt to even out lift along the blade, the downwash at the tips is still more simply because the blade is going faster there.

     

    I'm told that the blades on the Wessex were put into a large vice and twisted!

     

    cheers

     

    Phil

  3. Sorry, I should have said that the middle part has no drag (those single malts again):

     

    At the tip, the TR lies behind the axis of rotation - in the driving region, it is on the axis, and it is in front at the root. At the tip, therefore, you get a small portion of drag, just as you would get in normal flight. In the driving region, all you get is rotor thrust, and at the root, the horizontal part of TR assists rotation and tries to accelerate the blade (i.e. it becomes autorotative force). At constant rotor RPM, rotor drag = autorotative force so there is zero torque at the hub if you ignore hub bearing friction.

     

    Thus, the outer part is always providing lift.

     

    Phil

  4. Hope this helps without sending you to sleep (I'd love to know why you want to know!)

     

    In autorotation, the rotor drag that is normally dealt with by engine power is now handled by the air coming up through the disc. Induced flow now comes from below, so the angle of attack is now the combination of pitch angle and induced angle, so it is rather large.

     

    Juan de la Cierva, of autogyro fame, found that the wing of an aeroplane, when gliding, not only provides lift, but a forward pull as well, and this quality is made use of in autorotation to keep the blades rotating, since, if you tie one end of a blade to the hub, the remainder will want to turn in a circle.

     

    The inner 25% of each blade is stalled, and the outer 30% is providing a small drag force (in other words, it is being driven). The middle part of each blade is therefore the only part providing lift. The only negative lift is required by the tail rotor because the fuselage is now trying to go in the same way as the rotor blades, due to friction.

     

    As you increase speed in autorotation, the driving region moves towards the retreating blade side (together with the stalled region) until it touches the edge, where the angle of attack is larger, which is your power-off VNE, because once the driving region goes beyond the edge of the disc, the surface area of the driving region is reduced, resulting in rotor decay. At this point, the advancing blade contains a higher proportion of the driven region and the retreating blade contains more of the stalled region, with a reduction in the size of its driven region.

     

    Phil

  5. George - whilst taking on the comments about employment above, it also needs to be pointed out that you have to think anything about 6 months to a year ahead in this industry - frequently you are doing stuff for which you have no valid reason, only to find later that it was exaclty the right move! Go figure and follow your heart.

     

    When companies are taking on pilots, they're not going to wait while you get your licence - they will want you to start NOW, if not sooner, so you need all your ducks in place. Having said that, there's no need to rush right now - take your time and do the job properly.

     

    There are tons of good schools, some mentioned above - ones I have personal experience of and can recommend are Bighorn at Springbank, Premier at Pitt Meadows and the Central Helicopter Academy in Ontario, in no particular order. Convenience plays a big part.

     

    Good luck

     

    Phil

  6. Does anyone have a "manual" or graphics on this? Great topic.

     

    CJM

     

    I've tried to encapsulate a lot of the bits of paper floating around crewrooms with this stuff in The Helicopter Pilot's Handbook, but heaven knows there are still some gaps - there's simply not enough space! (with special thanks to the stuff Brad Vardy wrote for CHL). Eric Stoof has a good company book for his students if you can get hold of one. There are doubtless others!

     

    Phil

  7. And what sort of light twin are we talking about? The 902 does indeed have good OEI performance, but it is simply too big not to p*ss the neighbours off around there. The only light twin that won't do that is the twinstar, which is simply an expensive way of carrying around two Allison 250s! The F1 and F2 models will run out of puff on a hot summer's day, and require you to be below 2100 kg for the Cat A performance required for such a rescue. Which leaves the N! In Ruedi's case he then has to fork out for new tools and engineer training and a whole load of new procedures, plus spare gearboxes and engines to cope with Eurocopter's slow turnaround times, although those might be better in Canada than they are in Europe.

     

    With current equipment, I'm not a great advocate of the "twin automatically being safer" mentality, although in the big picture there is probably a 5-10% safety margin overall for most machines if you're talking about corporate liability, depending on when the stove quits. It certainly didn't help the Cougar guys, God bless 'em.

     

    Phil

  8. I wouldn't have said that Ruedi is an "experienced" rescue pilot, given that his main job is flipping round the Falls every 9 minutes, but he does get training, and he was there on the spot. I've flown those machines and I would have had a go under the same circumstances, especially as I have had much practice hauling broken motor cyclists off mountains in fog with a jettie. Much the same risk.

     

    Obviously, there is a point beyond which it is plain that you will be doing no good, and the rescuee has to be let go, same as if you get a sight of the guy in the drink just when you get the bingo call. This is decision making and risk management at its best, but let's not be so politically correct, or worried about not being "a professional" that we don't even try in the first place! You surely have to give it your best within the limits available.

     

    Should the Forestry guys with the Longranger not have tried to rescue the woman in the icy river in the Potomac crash, or should they have waited for a twin?

     

    Phil

  9. 4 years supporting the Royal Ulster Constabulary, plus other forces in UK, and EMS, plus being fairly knowledgeable about Fire Service matters. Firemen and lifeboat people deserve a special place in heaven.

     

    Even if I wasn't, my comment still stands. The logic that you don't add another person to the emergency applies to the general public, in my opinion, who are not trained. Otherwise, what's the point in having emergency services if they're not going to pull you out of the sh*te?

     

    phil

  10. I say well done Ruedi. The 407 is a good ship, I know the maintenance is OK there (or at least it was) - you would have to at least try, surely! They were good odds, especially when a twin-engined helicopter is only safer when one engine fails!

     

    Wasn't there a recent video on here where someone blew a deer to the side of a lake with his downwash?

     

    As for emergency services - risking their lives is what they are paid for!

     

    Phil

  11. Hello,

     

    I will be taking flight trainning in the middle of this year. In the meantime i would like to start getting some "knowledge" .. What do you think of virtual at home flight simulation like FLIGHT SIMULATOR X and the appropiate controls?

     

    Happy flying!

     

    For basic flying, I would probably leave them all well alone, or at least don't take them too seriously (they are after all computer games) unless you are using a specialist sim like the Flyit.

     

    However, for procedural work, such as IFR, they can be very valuable aids, even on your desktop PC. Microsoft Flight Sim is rather "fluffy" compared to X-plane, but even X-Plane is not so accurate is some situations.

     

    cheers

     

    phil

  12. L3 - I hear you, but I didn't say I wouldn't hot refuel, just that I wouldn't do it with the controls unattended, hence training the first aid guy (when you've got a sticky customer having an alternative up your sleeve is always a good move!) My problem is, "operational necessity" is too often confused confused with "customer necessity", and we let the tail wag the dog too much.

     

    Freefall - thanks for your post, you make a good point.

     

    Phil

  13. Wiggins - you're not missing anything, but some customers might be. I've been run off a couple of jobs for not keeping running while refuelling with the controls unattended, which I still refuse to do - at least until I find a customer that will get me another licence or pay for any fines! To my mind there's something wrong if they can't stand a couple of minutes for rundown and startup, but there you are. As you say, it's a great opportunity for a break as well.

     

    Having said that, I can see that there are some occasions, such as being in a VERY remote place with no support, where keeping the thing going might be acceptable if the battery is at all suspect, but I usually train the first aid guy instead to do hot refuelling! He's usually sat in his truck anyway.

     

    BTW, it's very hard to tell some customers what your machine will or will not take! Some of them are real pocket experts with intelligence to match.

     

    As for the hydraulics, my military training said to turn the hydraulics off if the controls are unattended, but I can see the argument for not doing so.

     

    phil

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