Turning an Aircraft Carrier by Air Power.

Discussion in 'The Fleet Air Arm' started by Beau_Nidle, Jan 4, 2008.

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  1. Hello Folks.
    I'm new around here. I'm a civvie, and a military enthusiast and supporter.(whatever knickname that might incur, I'm sure there will be one, polite or not!).
    I heard an account of one of our aircraft carriers being manouvered in harbour by the positioning of aircraft on deck and the use of the thrust from their airscrews (Seafires or somesuch, I think).
    Can anyone confirm or otherwise this, please, and if possible provide any details if it did take place?
    Thanks.
    B.N.
     
  2. Any sources or dates to even hint at a half-serious/researched reply?

    [Contributor mode]
    From the little I know of such things I'd think rather unlikely to happen due to the fact that pilots won't necessarily take being lurched at XXXkts over the side if a) the ship rolls, b) the restraints tieing the aeroplane down break and c) the captain would like to know where he's going without having to fill in lots of paperwork and expect lots of interviews without coffee from very senior people sans happiness. However, I wouldn't say "No"... (though it seems apochryphal)
    [Here endeth contributor mode]
     
  3. It certainly did happen, and quite frequently during the 50's and very early 60's.
    HTP Hig The Pig was in the mob during that period, he will know more.
    RoofRat
     
  4. Like I said, I know little. :D I look forward to hearing more.
     

  5. I did a commish on a carrier early sixties.---------in harbour and going into harbour the only aircraft left on board are the squadron spare parts /defects.
    They all fly off before the carrier gets an alongside berth and rejoin when the carrier gets back to sea..

    Defective aircraft are lifted off onto a lighter .

    So I would say --no chance . Also as PNG says the chance of a fcuk up is very likely ---ties and stays for parked A/C are just that .


    :nemo: :nemo:
     
  6. Tugs?
     
  7. "The Bridges at Tojo-Ri", both the film and book by James Michener show how the Elmers did it on an ESSEX class CV.
     
  8. Ninja_Stoker

    Ninja_Stoker War Hero Moderator

    Welcome to Rum Ration Beau_Nidle

    Must admit I thought it was a complete wind-up due to the fact propeller driven aircraft such as a Seafire would have little thrust, certainly compared to jet aircraft. Wind affects a carrier trying to park far more than a suitably restrained aircraft could. Fuel-wise a tug would be far cheaper, less noisy & more fuel efficient, so it's difficult to understand, even if it were possible, why anyone would want to do such a seemingly impractical thing.

    The only other flaw in the plan is that ships entering/leaving harbour and aircraft on deck simultaneously, certainly in UK, tend to be a fairly rare event. I've seen a squadron of Harriers fly onto a carrier in harbour, but that's about it. That said:

    We watch with interest...
     
  9. March 1958, HMS Eagle went alongside in Toulon using`Operation Pinwheel`, Seahawk Jets on one side aft, and Wyverns on the other, i have a photo of it somewhere in my commissioning Book (Now theres a term that you dont hear anymore)
     
  10. chieftiff

    chieftiff War Hero Moderator

    I've heard this before but believed it to be an urban myth or possibly a wind up by the pilots/ squadron engineers. There is no reason why the aircraft couldn't be tied down and run at max thrust (how else do we function the engines) whether all the high power tie down slots are arranged facing one direction on an old carrier I'm not sure but they certainly aren't nowadays.

    The reason I believe it to be a myth is plain old physics: Every action has an equal and opposite reaction, if I line up say 10 jets all facing to Stbd and run them at max chat I could probably deliver c20000Lbs of thrust per jet (max chat from a Pegasus is c 23000 lbs) maybe a bit more for an older jet with reheat, so that is say 200000 lbs of thrust (lbs remember) or even 400000 lbs if we are feeling generous. The new Ark Royal weighs a mere 20600 tons compared to the old one of c70000 tons but we will use this anyway. So we have 200000lbs of thrust trying to move an object which effectively weighs 46 144 000 lbs, but worse than that it not only has to overcome the inertia of 46 144 000 lbs (although no friction which is a bonus) it also has to compete with the fluid within which that body is sat and displace a few thousand more tons. It all sound plausible until you think about it, aircraft move air to create thrust, they are light so they can get away with it, ships move water to create thrust........ inertia! every action has an equal and opposite reaction!!!

    Your Carrier might move, but you wouldn't really notice for a long long time.

    Edited to remove stupid acceleration equation which ended with no units and note that if Hig said it happened it obviously did, but I still don't believe it worked very well: HMS Eagle displaced 96 320 000 lbs empty. Nene engine (Seahawk) only delivered 5300 lbs of thrust although I have no idea how much thrust the prop of a Wyvern generates :thumright:

    On Googling operation pinwheel I did however find this image of the USS Medway
    [​IMG]

    and this quote from HERE

    "As we steamed up the coast of Japan, the Air Group Commander, CDR Marsh Beebe, called CDR Trum, the CO of the Corsair squadron, and me to his office. He told us that the prop squadrons would participate in an exercise dreamed up by the commanding officer of the ship. It had been named OPERATION PINWHEEL.

    The Corsairs and Skyraiders were to be tied down on the port side of the flight deck; and upon signal from the bridge, all engines were to be turned up to full power to assist the tugs in pulling the ship along side the dock.

    CDR Trum and I both said to Beebe, “You realize that those engines are vital to the survival of all the attack pilots. We fly those single engine planes 300 to 400 miles from the ship over freezing water and over very hostile land. Overstressing these engines is not going to make any of us very happy.†Marsh knew the danger; but he said, “The captain of the ship, CAPT. Wheelock, wants this done, so do it!â€

    As soon as the news of this brilliant scheme hit the ready rooms, the operation was quickly named OPERATION PIN HEAD; and CAPT. Wheelock became known as CAPT. Wheelchock. "
     
  11. I have actually seen this done once. Mid 70s HMAS Melbourne coming alongside Garden Island in Sydney. There was a civilian tug drivers strike, I think. Very noisy - S2G Trackers, which sounded like farm machinery anyway, running flat out while chained to the deck.
     
  12. Sorry Chief Tiff, I am not doubting your grasp of mathematics, but it worked.
     
  13. chieftiff

    chieftiff War Hero Moderator

    You should Hig, after 3 bottles of Snecklifter it seemed unlikely. This morning it seems the Eagle (with 20 Seahawks at max chat all facing to port) would have accelerated at 0.001 ft/s/s to stbd (without considering the resistance of water which obviously increases exponentially as velocity increases and will dramatically decrease that) I will work out what its max velocity would have been considering water resistance when I get a chance but you will be pleased to know that it worked (even if you already knew that because you were there it's always comforting to know what happened is possible :thumright: )
     
  14. I've been searching , with no success so far, for a picture I have seen of Victorious turning in Grand Harbour with the help of a whole line of ( as memory serves) Avengers and Skyraiders. I'll keep looking. I don't know of any instances of jet aircraft being used, but I would guess that it happened at some time. In the days of piston engined aircraft, it was used rarely because of engine life, excessive ground running caused too much wear and tear. I'll keep looking for the photo.
     
  15. Also , I believe the closeness of the buildings in Grand Harbour added to the effect of the propwash. ( N ow that's a term you don't hear too much in these days of paraffin burners!)
     
  16. I shall make the effort to post the picture, there are 4 Seahawks Stbd side and i think it`s 2 wyverns and 2 gannets port side aft. My maths is piss poor but if my fat mate floats in a swimming pool, i must have a hell of a strength to move him with a gentle push of my little finger.
     
  17. chieftiff

    chieftiff War Hero Moderator

    But your fat mate doesn't have a draught of 33ft over a length of 804ft trying to push against sea water at a density of 63lb per cubic foot, he doesn't weigh in at 96 million lbs either (I hope) I think I have all the figures I need now, will get on it. Can you remember how long it took and whether the ship was manoevred sideways or was it just a way of rotating the ship?

    PS 0.001 ft/s/s (from my last post) is a hell of an acceleration (after 10 mins she would have moved 180ft) which is why I think the resistance of the water is key to working out how fast the ship would have moved.
     
  18. Regardless of the maths, lets dispel the myth, 9th March 1958 HMS Eagle, sorry the piccie is`nt all that good but here it is and i was there.
     
  19. This is interesting. I remember the Film where the Air Group commander was p**sed off by the Carrier captain for using valuable A/C engine hours for unassisted berthing.

    If we consider a representative Carrier of the time, say, VICTORIOUS at around 25,000 tons with about 111,000 shp that could wind her up to near 30 knots. Berthing assistance could be a couple of harbour tugs, say, present day ADEPT Class at around 5,800 bhp a piece. What's that? a total assistance bhp of 11,600 (about 1/10th of the Carriers own machinery)? So, interestingly, just 6 EA Seafire/Firefly/Seafury at about 2200 bhp a piece could provide sufficient berthing assistance. A totally bloody stupid use of aviation, though, before one's even daft enough to consider using turbojets!

    I think we will find that at speeds less than a knot, hydrodynamic drag can be discounted. The runing in the swimming pool analogue.

    Higthepig, I must learn to type faster!
     
  20. FFS does it matter? It was done, end of.
     

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