Armstrong Whitworth AW.681 / HS.681

[GTX]

Hi folks,

Does anyone have detailed information on the British contender (and winner I believe) for the NBMR. 4 VTOL tactical transport aircraft requirement - the Armstrong Whitworth Type 681? All I have are these pictures:

Regards,

Greg

 

[Deino]

In the next Air Enthusiast there will be an article on this topic ... to be published on June, 23rd !

Cheers, Deino

 

[TinWing]

This is the Medway engined proposal.

This is the Pegasus engined proposal. Some variants were depicted with huge pods of lift engines suspended under each wing

 

[TinWing]

In the next Air Enthusiast there will be an article on this topic ... to be published on June, 23rd !

Cheers, Deino

Another Tony Buttler article?

His article on the military variants of the BAe 146 was the highlight of the November/December 2005 issue. Is Mr. Buttler planning a book on British transport aircraft?

 

[Antonio]

Tinwing,

I think the BAe 146 article was not from Tony Buttler. Tony wrote the FX/VFX one in the same issue.
I found the BAe 146 article a bit poor (information was not well structured) and only a couple of versions were illustrated
Mr Buttler articles and books are always very well exposed and estructured...and you can find drawings for almost every design.

Thanks for the info, Deino...I'm going to order a copy right now

 

[Sentinel Chicken]

Does anyone have any schematic illustrations of the Medway engine and how it differed from the Pegasus?

 

[overscan (PaulMM)]

Project Cancelled has a good section on AW 681.

The Medway version was STOL only, in its basic form. It had two rear mounted thrust deflectors on each engine pod. In order to offer VTOL, Rolls-Royce suggested R.B.175 lift turbofans carried in two underwing pods with 9 engines in each pod.

Project Cancelled does have a drawing showing the R.B.175 installation, but not the Medway installation.

 

[lark]

A.WW. 681

Long-range Stol military transport aircraft capable of development to
VTOL. Designed to spec. OR.351.
Shoulder wings and hight T tail.Fuselage upswept with loading doors
and ramp.

Four RR Medway RB 142 engines with vectored thrust nozzles.
Boundary- layer control with blown leading edges , flaps and ailerons.
Span: 40.84 m lenght: 31.75m height : 11.53m
max.payload:15.876 kg.Max range 7.725Km
Max cruising speed 0.71 above 7.620m

Cancelled: 2/1965


Several sources : most reliable - Armstrong Whitworth Aircraft
since 1913. Oliver Tapper
Putnam - UK

 

[Antonio]

Is Mr. Buttler planning a book on British transport aircraft?

I don't know if he is going to continue after its fighter and bomber series, but it would be fantastic to see US/Soviet/British/...Transport Secret Projects, and then ....Airliners/Trainers/ : :


Cheers,
Antonio

 

[Deino]

In the next Air Enthusiast there will be an article on this topic ... to be published on June, 23rd !

Cheers, Deino

Another Tony Buttler article?

His article on the military variants of the BAe 146 was the highlight of the November/December 2005 issue. Is Mr. Buttler planning a book on British transport aircraft?

Hmm ... I don't think !

He's currently working on the first book of US secret projects to be finalised until mid September ... what's next ... I hope something on "Chinese" ;D

Cheers, Deino

 

[TinWing]

Does anyone have any schematic illustrations of the Medway engine and how it differed from the Pegasus?

The Medway was a Rolls Royce design, first unsuccessfully promoted in the late 50s and then revived unsuccessfuly before being abandonned in the mid-60s. The Spey was a scaled down Medway. The Medway proposed for the HS681 had a pair of thrust diverters.

The Pegasus was a Bristol-Siddeley design, with design elements based on both the Orpheus and Olympus. Confusingly, both the familar four poster Pegasus and a conventional straight-through Pegasus were proposed for the HS681.

 

[Jemiba]

That's what I've found in Derek Wood's "Project Cancelled" :
1 - The HS(AW) 681 with four RB.175, using deflectors and a rotating cascade
2 - The HS(AW) 681 with four Medways and 18 RB.162-64 lift engines
3 - The AW 682, a civil freighter development with four Pegasus without vectoring
4 - The HS.802, the last attempt to safe at leat some of the development work,
by mating the the 681 fuselage to the wing of the Comet 4 .

 

[TinWing]

That's what I've found in Derek Wood's "Project Cancelled" :
1 - The HS(AW) 681 with four RB.175, using deflectors and a rotating cascade
2 - The HS(AW) 681 with four Medways and 18 RB.162-64 lift engines
3 - The AW 682, a civil freighter development with four Pegasus without vectoring
4 - The HS.802, the last attempt to safe at leat some of the development work,
by mating the the 681 fuselage to the wing of the Comet 4 .

From what I've read, HS681-2.jpg would seem to indicate the most definitive configuration. It would seem that a selection between the Medway and Pegasus hadn't been made at the time of cancellation, although the RR engine seems to have been the favorite for commercial reasons.

It is also interesting to note that the earlier AW681 configurations have a broader, more upright tail than later proposals. I do have to wonder why the vertical tail became more swept and perhaps even a bit smaller in area?

The HS.802 was a final, rather sad "hail mary" attempt to salvage the project. The use of the Nimrod (HS.801) wing would seem to make sense from an industrial standpoint, but the reality was that any Comet derived wing was a poor choice for a STOL transport.

 

[Thorvic]

In the next Air Enthusiast there will be an article on this topic ... to be published on June, 23rd !

Cheers, Deino

Deino

Just checked the Air Enthusiast website and its not one of Tonys but rather the VTOL specialist Mike Pryce (aka Harrier on What-if). Had a good look at the display models last Saturday at Midland Air Museum so now looking forward to the article

Cheers

Geoff

 

[PMN1]

Are their any specifications for this around?

 

[TinWing]

Are their any specifications for this around?

There were some very limited specifications in Derek Wood's "Project Cancelled," Appendix 6, page 250.

 

[lark]

All you ever wanted to know about the AW 681
(and much more) is now in

Air Enthusiast No.124 - July/August 2006.

 

[TinWing]

All you ever wanted to know about the AW 681
(and much more) is now in

Air Enthusiast No.124 - July/August 2006.

Will the AS 681 article ever make it to print?

I thumbed through the July/August issue of Air Enthusiast at a newstand, and I didn't see anything about the AW 681?

It isn't in the September/October issue, either?

 

[overscan (PaulMM)]

I've seen the article in Air Enthusiast. It was a beautiful article!

I can't remember which issue it was, but it was defintiely there!

 

[TinWing]

I've seen the article in Air Enthusiast. It was a beautiful article!

I can't remember which issue it was, but it was defintiely there!

Let's see, the July/August issue was the one with the Gannet on the cover? That was the issue I quickly thumbed through. I must have just overlooked the AW.681 article because I doubt that a low circulation magazine would have a separate printing for North America.

Did the article actually have any new line drawings or specifications?

 

[lark]

Air Enthusiast July/August 2006 -- No.124

pages 10 to 17. Text by Michael J. Pryce.
Excellently written.Profusely illustrated.
There's even a cutaway drawing of the turboprop AW.680.
Highly recommended.

 

[cxmech]

I've recently acquired a brochure
it covers S.T.O.L MILITARY TRANSPORT TO O.R 351 TYPE NO. AW 681,
published for hawker siddley aviation limited may 1961.

not sure what sort of interest this would be to anybody I'm thinking of selling it on.
may be eBay. but i have a few photo's if any body wants to mail me I'll send them on.

i've added some scanned pages from the brochure.

 

[Thorvic]

Yes Please

I'm currently building one in 1/72 scale so any information is always handy

Cheers

Geoff

 

[cxmech]

hi
i've attached a zip file of some scanned files.

 

[flateric]

Thank you very much! Fan-flap concept is a real beauty)

 

[overscan (PaulMM)]

CXMech, I have posted slightly edited versions of your originals. Please see private message for details.

 

[TinWing]

Image img010.jpg would seem to depict a concept that looks very much like a scaled up Argosy.

 

[Thorvic]

That the AW680 a steeping stone project from AW670 Argosey to AW681 Aldershot

 

[TinWing]

That the AW680 a steeping stone project from AW670 Argosey to AW681 Aldershot

I would assume that the AW680 was Tyne powered and had a somewhat earlier timescale. Was it originally conceived as a competitor for the strategic requirement that the Belfast eventually won?

The internal dimensions of the AW.681 have always been a mystery to me? It would seem as if this design had a somewhat larger fuselage diameter than the Transall or Hercules, but how close was it the earlier Belfast?

I have never been entirely clear on the specifications for the 681 project (wing area, etc) and I really do have to wonder how this early (1961!) proposal differed from the definitive design.

 

[cxmech]

I've had a quick look through the brochure it states that the lifting engines considered are the Bristol Siddeley BS59/7, at 8,000lbs rating or alternatively Rolls Royce RB175 fan engines.
for the overall dimensions for the fuselage are length 105ft, max width 15ft 2".

 

[cxmech]

as this brochure refers to 4 different a/c configurations, there are variations on the engines used.
it does refer to using 4 BS 53 engines with hawker P 1127 type nozzles, on the turbo-jet with deflected thrust and blown flaps(ref jpg's).

 

[overscan (PaulMM)]

Now on Ebay @ £4.99

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220163991674

 

[alertken]

Farnborough, Sept.63, model 681 with Pegasus. Days after, ITP for RB.141. NBMR4, Do.31, was Pegasus on prototypes. MoA view that BSEL would not cope with BOl.593, BOl.22R, BS100, Pegasus for Do.31 and for 681, while RR was, well, empty, bar weird liftjets.

 

[overscan (PaulMM)]

Have you considered donating the original document to the Midland Aviation Museum at Coventry? They have a number of Armstrong Whitworth exhibits including models of the AW 681, I'm sure this document would be well received there.

 

[cxmech]

i'll drop them an email see if they are familiar with the brochure, i'll let u know what they say.

 

[overscan (PaulMM)]

AW.681 models abound at the Midland Air Museum. Highly recommended for anyone with even a passing interest in the AW.681. Will post some details from brochure later.

 

[overscan (PaulMM)]

3 view of AW 681 plus some design studies

 

[SteveO]

Does anyone have any schematic illustrations of the Medway engine and how it differed from the Pegasus?

The Flight archives have plenty of info on the Medway http://www.flightglobal.com/pdfarchive/view/1963/1963%20-%202233.html

 

[overscan (PaulMM)]

More details.

 

[hesham]

That's what I've found in Derek Wood's "Project Cancelled" :
1 - The HS(AW) 681 with four RB.175, using deflectors and a rotating cascade
2 - The HS(AW) 681 with four Medways and 18 RB.162-64 lift engines
3 - The AW 682, a civil freighter development with four Pegasus without vectoring
4 - The HS.802, the last attempt to safe at leat some of the development work,
by mating the the 681 fuselage to the wing of the Comet 4 .

Hi,

http://www.flightglobal.com/pdfarchive/view/1963/1963%20-%200370.html