View Full Version : Spruce Goose a WIG Aircraft?


VS1711
22nd Sep 2006, 15:51
I know it's not exactly topical but I recently read an article on Russian Ekranoplanes (Wing in Ground Effect aircraft). I'm also reading a Howard Hughes biography. My question is this; Has it ever been established whether the Spruce Goose had enough power to climb out of the Ground Effect or was it's short flight a one-off because it couldn't?



Rainboe
22nd Sep 2006, 16:09
I'm fairly sure that if it had the power to lift off out of the water, it could have climbed out of ground effect. I think the short flight was a checkpoint on the development program where Hughes earned a large ongoing payment from the government for the program for having actually flown the thing. The reasons for the cancellation could be anybody's guess- it has always been a mystery and were never revealed. I suspect the government maybe had let Hughes know they had lost interest.

ORAC
22nd Sep 2006, 16:26
The only flight stayed so low and was for such a short time because it was totally unauthorised for the exercise, which was a taxi trial. When the chief designer later asked Hughes whether he actually meant to lift it off the water, Hughes replied, "You'll never know." It is generally thought he did it deliberately just to prove it could fly to the critics, but with an excuse where he could deny it was deliberate.

Could it have flown out of ground effect? Undoubtedly, whilst it is said to have been underpowered, if it had the thrust to break the water suction and get airborne it undoubtedly had the power to climb well out of ground effect, particularly without a cargo payload onboard, and probably get close to its planned ceiling of around 29,000ft.

But even true WIG aircraft can operate out of ground effect, the Ekranoplan (http://www.globalaircraft.org/planes/lun_ekranoplan.pl) had a ceiling of over 24,000ft. They are just not very efficient out of their design envelope.

DUB-GREG
22nd Sep 2006, 16:41
Hi i also read the Hughs auto bio.

I enjoyed it very much, he was a true lover of aviation, all be it a bit of a freak when it came to hygeine etc.

And i cant believe you called it the Spruce goose... Mr Hughes hated that, its the Hercules! : )

The plane did fly, even though it wasnt for very long. He was ment to bring it out for a taxi run, but he couldnt resist, so the let it fly for a few seconds then landed again.

Have a good weekend.

Slasher
23rd Sep 2006, 04:26
I read the book too and reckon it mustve been a bloodey top emotion indeed for Hughes as the Hercules lifted off the water - to go through the political and bureucratic crap he did and still get it to fly. Mustve been the bestest feeling in the world! :ok:

ChristiaanJ
23rd Sep 2006, 13:01
In the same context, I seem to remember the Dornier Do-X flew some of its long distance trips in ground effect, not because it couldn't climb out of it (it could), but because it gave a longer range

ZAGORFLY
24th Sep 2006, 14:36
Hi i also read the Hughs auto bio.

I enjoyed it very much, he was a true lover of aviation, all be it a bit of a freak when it came to hygeine etc.

And i cant believe you called it the Spruce goose... Mr Hughes hated that, its the Hercules! : )

The plane did fly, even though it wasnt for very long. He was ment to bring it out for a taxi run, but he couldnt resist, so the let it fly for a few seconds then landed again.

Have a good weekend.

Thank you DUB,
Hercules story is now on display in Mc.Minville (OR) at the Evergreen Museum.
Is is splendid. like a 747 SP with ite 8 engines. Hercules is the name but spruce goose become its web ... bye

411A
24th Sep 2006, 14:55
Those unfamiliar with the aerodynamic aspects of the H-1 design, might be interested to know that during the brief flight in Long Beach harbour, severe empanage vibrations were noted, and after the aeroplane was docked, and Howard disembarked, he mentioned to one of his desin engineers that...'this thing will never fly again'.

Well known at the time in Southern California aviation circles amongst Hughes employees.
'Tis a fact.

barit1
25th Sep 2006, 13:04
It was designed at a time when very large logistics aircraft were in their infancy, and it used the best propulsion available at the time, but there were still plenty of unknowns. At best it could have been considered an R&D bird.

Without payload, it might possibly have reached 29K before draining the fuel tanks!

The wood construction was of course to overcome a foreseen strategic aluminum shortage, which never fully materialized.

And 224 cylinders, 448 spark plugs????

BTW - model designation was I believe HK-4, for Hughes-Kaiser. I don't recall what shipbuilder Kaiser's involvement was. The H-1 was the famous (or notorious, because competitors refused to race against this ship) prewar racer.

evansb
25th Sep 2006, 13:38
I too have read about empennage vibrations on the maiden flight, specifically coming from where the vertical stabilizer joined the fuselage.

Flight out-of-ground effect? I think so, just watch the film of the initial flight where the Hercules actually climbs well enough so that Mr. Hughes actually has to input some DOWN control. I don't think that was done to increase airspeed, due to the low altitude. I don't know what flap settings were used, so it may also have been a result of flap retraction and subsequent trim adjustment.

411A
26th Sep 2006, 07:20
Yes, HK-4 is was.

My Dad had a coffee table made from a piece of spar cap, 28-ply Birch.
Beautiful wood, superbly crafted.
As I recall, Henry Kaiser pulled out of the project due to his doubts about Hughes ability to actually get the airplane built.
After all, Kaiser, being one very smart and successful businessman, who was the prime contractor on Hoover Dam (The Six Companies), completed two years ahead of schedule and under budget, had the noteable distinction of having his company build Liberty ships...4 per day were turned out toward the end of the war.
With all that success, Hughes was seen as a liability, I believe.

ORAC
26th Sep 2006, 07:30
Nomenclature was either HK-1 or H-4.

barit1
26th Sep 2006, 12:16
Very interesting!

According to the FAA Civil Aircraft Register - Advisory Circular 20-6D, July 1, 1965 - NX37602 was registered to Reconstruction Finance Corp, the same agency which sold thousands of WWII surplus aircraft after the war. Registers of this vintage generally included thousands of aircraft no longer airworthy.

The type code is 447 01, a Hughes model 10, and the serial number is HK1.
Year of MFG 1947, eight P&W Wasp Major engines. :8