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Viewing 15 posts - 541 through 555 (of 3,326 total)
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  • in reply to: World Piston Engined Speed Record Attempt #838790
    Beermat
    Participant

    Good. Thanks – the website said Friday as well. I was wondering whether it will go so fast it will (have already) punch(ed) a hole in the space-time continuum.

    in reply to: World Piston Engined Speed Record Attempt #838833
    Beermat
    Participant

    Is that SATURDAY 2nd, or has it already happened? Confused.

    in reply to: WT markings on aeroplanes #838989
    Beermat
    Participant

    As I understand it it does stand for ‘Wireless Transmitter’ – the stencils mark the points at which earthing straps are attached so that different parts do not build up different charges. The primary source of charge would be the W/T. Interestingly there is often a DTD number next to them – this specifies the paint, which needs to have particular electrical properties as well.

    Please don’t ask me to name my sources – it’s been a long time!

    in reply to: General Discussion #227827
    Beermat
    Participant

    Tell that to a Bermudian: http://www.thebermudian.com/

    I guess they didn’t go to a good enough school to know what to call themselves.

    in reply to: Seen On Ebay 2017 #839063
    Beermat
    Participant

    eBay are worried about being sued by big companies, so selling a copy of a ‘label’ design is something they will come down hard on, even if, as happened to Wyvernfan, the seller makes it clear it’s a copy.

    This shows that they do understand that they arguably have some liability when it comes to what is sold – it’s just that they know they can’t be touched by anyone who can’t afford corporate lawyers.

    in reply to: World Piston Engined Speed Record Attempt #839283
    Beermat
    Participant

    My reply disappeared. Short version is 5.6m diameter and 750 rpm. Twist slightly less than stock P-51. Cruise at 440 (faster than P-51) rotates at 480 (slower than P-51) combined 660. Tip speed exceeds Mach 1 in cruise above 40,000ft. Agree that rear set will be different – greater pitch – as need to bite into faster air.

    Re. S6 prop.. now there’s a can of worms.

    in reply to: Seen On Ebay 2017 #839495
    Beermat
    Participant

    The problem is that eBay know perfectly well that fakes are peddled via their site in vast quantities, across the globe and in all kinds of fields of interest – archaeological relics, motoring, literature, philately, you name it. It’s a multi-million pound industry.

    If they were a scrupulous organisation they would listen when people call out the fakes – the way a council street market regulator would. Sadly they are not.

    in reply to: World Piston Engined Speed Record Attempt #839665
    Beermat
    Participant

    Had a good rummage around for images and it appears there is nothing unusual at all about the aerofoil. Just the usual internet spin-out from some random post. It seems it started with someone not associated with the project claiming they had recently scanned the ‘new’ wing with LIDAR. Hmmm.

    In fact she is little visibly changed from her purple incarnation, which already had a few adverse-pressure-reduction and shock-avoiding things going on. It would be very interesting to see what AP inc have changed to make 550 mph now viable with this airframe and engine. As HP111 said, one would expect something more radical than a paint job. Must be under the bonnet?

    in reply to: World Piston Engined Speed Record Attempt #839731
    Beermat
    Participant

    Well, every day is indeed a schoolday. Some very interesting figures here: http://www.machinedesign.com/recreation/unlimited-air-racers-ultimate-hot-rods

    It seems racing Merlins are expected to turn at 3,400 rpm, and the ‘racing’ gear ratio is .42. So prop speed is more or less the same as stock.

    The article says that race teams like to have prop tip speeds at an apparently optimum Mach 0.8. To do this at 550 mph would mean a prop diameter smaller than stock. So there ya go.

    in reply to: World Piston Engined Speed Record Attempt #839736
    Beermat
    Participant

    Here’s a prop on a supersonic aircraft – very interesting article: http://fighterwriter101.blogspot.co.uk/2015/08/the-xf-88b-voodoo.html

    in reply to: General Discussion #227874
    Beermat
    Participant

    How on earth do I know? Because I have been there, on the shop floor. Have you? You got me there, though – I am now going to go away and Google Fred Kite (Edit: I now have. Character from a 1959 Ealing Comedy – or ‘contemporary satire’ in John’s world).

    There are a lot of very poor (academically and in terms of attitude) university graduates out there. This is because there are now a large number of essentially commercial entities calling themselves universities who will take and matriculate anyone who can pay. This is the change that has happened, and it takes a lot of truth-mangling to make this the fault of left-wing influence on state education provision.

    Eton kids empathising with Aldi Customers made me laugh – do you know how ludicrous that concept really is? Then I stopped when I realised that this is the problem we have – these people do end up running the country.

    in reply to: World Piston Engined Speed Record Attempt #839787
    Beermat
    Participant

    In reply to Hooligan’s mention of the prop – I would be very surprised if this is the one selected for an aircraft ‘tuned’ to 550mph, as the people behind the attempt have it. With that much twist the root section would be pushing the aircraft backwards with the effective parts at a suitable angle for thrust. This does look like a thin section high-speed blade, just not one optimised for flight with a tip rotational component of just 500mph and a forward speed of 550mph. Imagine the prop tips pitched at over 50 degrees to meet this – and then picture where the roots would be – essentially backwards.

    This is the right amount of twist for those sort of speeds.. (yes, they do turn half as fast – but they are twice the diameter!)

    [ATTACH=CONFIG]255497[/ATTACH]

    Unless they are running the prop ungeared? Then the angles might make sense – tip speed 1,200 mph.

    Interestingly, running normal .477 reduction gearing and assuming 3,000 rpm and a 3 metre prop the tips would be right up against Mach 1 at 550mph forward speed (around about 332 m/s combined, which is the nominal speed of sound at 6,000ft). No doubt one would be able to hear when that happened.

    Also I am interested in why they made the root thicker – this would make wing/fuselage interference worse. Are you sure this is the right way round? Looking at the image the tips appear thicker.

    in reply to: General Discussion #227887
    Beermat
    Participant

    No, just manipulated.

    John, have you considered that your view of what constitutes an education – for example, I’m sure it involves learning the Kings and Queens of England by rote – is exactly what employers find useless and what these people you call ‘lefties’ but whom I prefer to call teachers are trying to move away from.

    By the way, that Nelson story is bunkum. It is a poor education that leaves a man accepting this nonsense as news.

    I would be interested to see how a product of such ‘beacons’ as Winchester or even Eton would get on at an interview for Aldi. If they weren’t laughed out of the interview room they wouldn’t last five minutes on the shop floor. Frankly you are confusing two things when you talk of the excellence of these private institutions then decry a lack of preparation for real-life jobs.

    in reply to: General Discussion #227891
    Beermat
    Participant

    Tony, the British Government (ie ministers in their paid capacity of department heads, not MP’s) draft laws and then MP’s vote on them. It is deliberately that way to separate Parliament from Government.

    The EU follow the same system, only more assiduously.

    Constitutionally British ministers are not allowed to be democratically elected MP’s, even though most are. It is a law that has been ignored since Walpole. Ours is a less pure system than Brussels, and runs on a flouting of its own rules.

    in reply to: General Discussion #227988
    Beermat
    Participant

    As soon as someone finds something to negotiate with they might. But right now I’m ******** if I know what that is. We used to be able to say ‘we’ll walk out’.. we had the power of veto. When will the Bullxiters understand what the situation now is?

Viewing 15 posts - 541 through 555 (of 3,326 total)