The Short Mayo Composite

The Short Mayo Composite is the name given to a piggyback long-range seaplane/flying boat combination produced by Short Brothers to provide a reliable long-range air transport service to the United States and the far reaches of the British Empire and the Commonwealth.
Background
Short Brothers had built the Empire flying boats which were capable of operating long range routes across the British Empire but could only attempt the trans-Atlantic route by replacing passenger and mail-carrying space with extra fuel.
It was known that aircraft could maintain flight with a greater load than is possible to take off with; Major Robert H. Mayo, Technical General Manager at Imperial Airways (and later a designer at Shorts) proposed mounting a small, long-range seaplane on top of a larger carrier aircraft, using the combined power of both to bring the smaller aircraft to operational height, at which time the two aircraft would separate, the carrier aircraft returning to base while the other flew on to its destination. The British Air Ministry issued Specification "13/33" to cover this project.
Development
The Short-Mayo composite project comprised the Short S.21 Maia, a modified S.23 C class flying-boat, and the Short S.20 Mercury seaplane, the latter attached to a pylon mounted on top of the fuselage of the former.
Although based upon the "C-Class" Empire boat, Maia had considerable modifications from that design: an increase in total wing area from 1,500 ft2 (139.5 m2) to 1,7502 (162.5 m2); the engines were mounted further from the wing root to provide clearance for Mercury's floats and the fuselage was swept up towards the tail to raise the tailplane relative to the wing. Like the Empire boats, Maia could be furnished to carry 18 passengers. Maia first flew (without Mercury) on 27 July 1937, piloted by Shorts' Chief Test Pilot, John Lankester Parker.
The upper component, Mercury, was a twin-float, four-engine seaplane crewed by a single pilot and a navigator, who sat in tandem in a fully enclosed cockpit. There was capacity for 1,000 lb (456 kg) of mail. Mercury's flight controls, except for elevator and rudder trim tabs, were locked in neutral until separation. Mercury's first flight, also piloted by Parker, was on 9 August 1937.
"All eight engines were used during combined flight but the controls of Mercury were locked. The airfoil designs of the two aircraft were such that Mercury's wings were carrying the major part of the air load at the speed and height chosen for separation. Safety locks prevented separation until this speed and height were reached and both pilots had an unlocking handle, both of which had to be pulled to cause release.
The first successful in-flight separation was carried out from the Shorts works at Borstal, near Rochester, Medway, on 6 February 1938, Maia piloted by J Lankester Parker and Mercury by Harold Piper. Following further successful tests, the first transatlantic flight was made on 21 July 1938 from Foynes, on the west coast of Ireland, to Boucherville,[5] Montreal, Canada, a flight of 2,930 miles (4,715 km). The Maia, flown by Captain A.S. Wilcockson, took off carrying the Mercury (piloted by Captain, later Air Vice Marshal Don Bennett), Mercury separating from the carrier aircraft to continue what was to become the first commercial non-stop East-to-West transatlantic flight by a heavier-than-air machine. This initial journey took 20 hrs 21 min at an average ground speed of 137 mph (220 km/h).
The Maia-Mercury composite continued in use with Imperial Airways, including the Mercury flying to Alexandria, Egypt, in December 1938. After modifications to extend Mercury's range, it subsequently established a record flight for a seaplane of 6,045 miles (9,728 km) from Dundee in Scotland to Alexander Bay (in South Africa) between 6 and 8 October 1938.
Only one example of the Short-Mayo composite was built, the S.21 Maia with the registration G-ADHK and the S.20 Mercury (G-ADHJ). The development of a more powerful and longer-range Empire boat (the Short S.26), the further development of in-flight refuelling and the outbreak of the Second World War combined to render the approach obsolete. Maia was destroyed in Poole Harbour by German bombing on 11 May 1942. Mercury was flown to Felixstowe for use by 320 (Netherlands) Squadron RAF a Dutch seaplane reconnaissance unit serving with the Royal Air Force at RAF Pembroke Dock. When this squadron was re-equipped with Lockheed Hudsons, Mercury was returned to Shorts at Rochester on 9 August 1941 and broken up so that its aluminium content could be recycled for use in the war effort.

[@ronjon7942]

Two gorgeous craft in one episode.

[@HeadoftheSeniorClass-en6qp]

Great to have this here for aviation addicts and backstory buffs alike!

[@oldarf]

Beautiful stuff,reminded me of my very first dinky toy that I purchased in 1939 and have always rembered it,thank you,those were the days.I was talking to a fellow collector of Dinky toys he had not heard of this,and I can prove it did exsist. GREAT.

[@pyed1]

Amazing footage,great story and history. thanks for putting on you tube.

[@seftonwallet]

Wonderful footage, thanks for posting!

[@adriaanboogaard8571]

Very interesting Video. The only time I was fortunate enough to see something similar in person was the N.A.S.A. Space shuttle piggy back on a 747 take off.

[@diplomatiqueTM]

My grandfather Jim McLaughlin was one of the engineers who developed Mayo Composite. He used the concept later in life to help put the Space Shuttle on top of the 747. Pop was the Chief Weights Engineer of Boeing's Jumbo and helped get the 747 off the ground. Having stripped weight it was an incredible achievement to put the Shuttle on its back.

[@gixergs]

Sadly they have even built on the slip now the only Short Bros building left is the Main Hangar at BEA Systems near Rochester Airport where the Land Planes were built. Apart from a few street and building names there is no reconigtion made to the Shorts Bros.The Last flying Sunderland "Sir Arthur Gouge" was based at the Dockyard many years ago and I was lucky enough to see her fly but now she lives with Kermit Weekes in Florida at the Fantasy of Flight Museum. Thank You Gix.

[@Bomberguy]

No problem, thanks for the comments

[@randlerobbertson8792]

Great footage.....

[@michaelegan6092]

Who are the idiots who disliked this film.I would like to see their engineering credentials.

[@alanc6781]

KZbin is now available in Institutions for the insane.

[@mrrolandlawrence]

oh the irony that at the same time the brits had scuppered frank whittles turbojet that could have easily been the core for those big HP turboprops!

[@alanc6781]

Over the years various British governments have done much to hinder progress in different fields of endeavour. Some were stupid decisions, some were deliberate.

[@Bomberguy]

The problem was head winds on the east to west crossing. With tail winds on the west to east crossing they didn't need as much fuel

[@Larrikins54]

The pilot of 'Mercury' was Don Bennett, an Australian-born pilot who when WW2 broke out joined the RAF. He went on to form and lead the Pathfinder Force which radically improved navigation and bombing accuracy in Bomber Command in WW2.

[@johnjephcote7636]

and BSAA postwar.

[@ronjon7942]

I read about him and his crews in McKinstry’s “Lancaster.” Amazing. But then, all of Bomber Command was amazing.

[@MrJohnmci]

My wife's uncle. Still plenty of Queensland Bennetts around

[@rolko52]

Reminds me of the Space Shuttle return flights to KSC.

[@guyhalsall1579]

My mates grandad is the radio operator on the mercury mr albert coster

[@johnjephcote7636]

In the early fifties I had the Dinky Toy seaplane upper half. The C Class lower part was not available. I knew what it was from the pre-war Odhams 'Wonders of the Modern (ie 1930s) World'.

[@v8pilot]

How did Mercury return home from where it had got to, without a second Maia to get it airborn?

[@Bomberguy]

Major Robert H. Mayo was the co-designer. The concept is known as the Short-Mayo. Maia is the name of the mother ship.

[@pauleveritt3388]

Originated the Minstrel concept.

[@jonzflicks]

Just a passing thought: If Mercury was too heavy with petrol to lift away from the water, how did she get back to Uk from Canada?

[@bazza945]

It was only suitable for carrying airmail and some freight. I recollect Mercury's flight time was around ten hours. After all that effort the service was more a publicity stunt rather than a useful service.

[@curbyweaver4606]

A couple of JATO (jet assisted take-off) units would have lifted this nicely.

[@diabeticalien3584]

I would pay to see that thing take off with JATO.

[@curbyweaver4606]

Flying boats were a great idea. Turning lakes or bays into airports. Your idea is a great one. It sure would have simplified take-offs. Too bad JATO's came online a bit late to enrich the golden era of flying boats. I wonder if they would have been economical given the passenger & cargo market of the day vs the cost of two JATO's.

[@rogerturner5504]

G-ADHD wasn't used because it wouldn't pay attention.

[@markmnorcal]

GO MAYO GO!

[@b.r.buckeyeman460]

Did the small plane make many Atlantic crossings. ?

[@space_cowboy_cops3933]

Holy hell this is ridiculous.

[@MrMoorkey]

Flip that...this one came first.