Last week, The People’s Mosquito shared a video of their patron, the irreplaceable Capt. Eric “Winkle” Brown, discussing his role in testing the de Havilland Mosquito for carrier operations.

Yes, you read that right: While the largest carrier-borne aircraft in service anywhere was the 10,545 lb Grumman Avenger (a big bird by any standard), the British were working out how to get on and off a boat in their 20,000 lb Wooden Wonder!

As the pilot who has officially flown more aircraft types than anyone ever (an amazing 487), Brown should need no introduction. But just in case, you can get to know him here.

In the clip, he starts by reiterating his view that the Mosquito is one of the three great British aircraft of World War Two – along with with the Spitfire and the Lancaster. That’s why he has accepted the role of patron for an organisation dedicated to returning just one to UK skies. Doing so will be a £5.5 million gift to future generations and a singular tribute to the 7,781 Mosquitoes built.

But getting back to that carrier experiment…

Highballs and battleships

The seaborne Mosquito can trace its history back to Barnes Wallis and his bouncing bombs, later made famous by the 617 Squadron ‘Dambuster’ raid of Operation Chastise. The original, smaller bouncing bombs, codenamed Highball, had been conceived by Wallis as a navy weapon for attacking capital ships in their ports.

Looking for ways to destroy the Nazi battleship Tirpitz – sister to the Bismarck (sunk in May 1942, see our ‘That pilot’ post) – Winston Churchill revived the idea in a memo sent in early 1943.

As it happened, the Royal Air Force and Navy would use more conventional methods to keep Tirpitz out of action.

However, the RAF did realise that the Mosquito could deliver Highballs with its characteristic speed and accuracy – and a plan for attacking Japanese capital ships with carrier-borne Mosquitoes was devised.

Enter Eric Brown.

A big problem

As the Royal Navy’s most experienced test pilot, Brown was asked to take on the near-impossible task of operating the DH98 from ships. It was an awkward request, not least because the carrier’s

arrester gear would limit the Mosquito’s landing to a maximum of 83 mph – against a published stall speed of 110 mph. They were going to need quite some wind over the deck.

What’s more, the Mosquito was heavier than anything that had been landed on a carrier before; and there was no guarantee that the airframe would be strong enough for the punishment of repeated deck landings.

I’m not going to spoil it for you, but the more reliable solution Brown and his team arrived at speaks volumes about the determination, genius and expediency of Britain’s war effort.

Watch the batsman

The first deck landing trials were conducted on HMS Indefatigable (R10) on March 25th and 26th, 1944. Brown and his engineer completed seven landings and take-offs on Indefatigable’s 766.5 foot (233.6 metre) deck without incident, flying their specially modified Mosquito FB.VI. It was the first time a twin-engined aircraft had ever been brought onto a carrier.

[Correction: The first twin to land on a carrier was a French Potez 565. See Ted Ward’s comment below.]

The Royal Navy brought their best batsman out to Indefatigable for the trials. And bringing a twin engined Mosquito onto the wires would turn out to be as dangerous for him as it was for the flight crew. With big Merlins on either side, the pilot couldn’t see a batsman in his usual post beside the arrester gear. So the batsman had to give his signals from the centreline of the flight deck, right down to the ‘cut’, then run for his life and duck under Mossie’s passing wing.

No wonder the Royal Navy invented the Mirror Landing Aid shortly after!

On the eighth landing of the day, Brown showed his remarkable skill when bolts holding the arrester hook sheared. Recognising, in a split second and from feel alone, that it was a hook failure and not a cable break, he fire-walled the throttles and dragged the Mosquito back into the air – falling over the port side thanks to the the engine torque, and dipping dangerously close to the water as they recovered airspeed.

In a second trial, on May 9th and 10th, Brown had to deal with the opposite circumstances when a cable did break and he brought the Mosquito screeching to a halt with brakes. Seventeen take offs and landings were completed with no other complications.

The Mosquito goes to sea

With the concept of a seaborne Mosquito proved, the Royal Air Force prepared for Highball attacks on the Imperial Japanese fleet, assigning two carriers and 24 aircraft to the mission. The specially trained No.618 Squadron RAF and their modified Mosquito B Mk.XVIs were deployed was far forward as Australia aboard HMS Fencer (D64) and Striker (D12) in December 1944. However bickering between RN and USN commands, and then Japan’s capitulation, meant No.618 would get a world tour but no action.

By coincidence, Indefatigable was on station in Japanese waters at the time of the surrender.

Still, from Eric Brown’s remarkable trials, the Mosquito TR. Mk.33 would be developed. Only fifty would be built, along with six slightly updated TR.37s, and the ‘Sea Mosquito’ entered service with the Fleet Air Arm in August 1946.

 

Sea legs, sea wings, and more

‘Navalising’ the big and powerful Mosquito took more than superficial changes. Major work was needed to provide manually folding wings, and de Havilland’s original rubber block suspension was replaced with Lockheed hydraulic oleo legs.

However the most obvious difference was two 12.5 foot (3.8 metre) four-bladed propellers hanging off 1,635hp Merlin 25 engines, a combination that delivered enough power to drag the aircraft aboard at its sub-optimal landing speed.

Most Sea Mosquitoes also had a distinctive ‘thimble’ nose, which covered state-of-the-art AN/APS-6 equipment. Others had a more streamlined, pointed nose shape, while the TR.37 carried later ASV Mk XIII radar inside a larger thimble. The Browning .303 machine guns had to be removed for both radar installations, but the battery of four 20mm Hispano cannons remained.

Strike force

The TR.33’s maximum take off weight was set at 22,000 lbs– one and a half tons less than the demonstrated 25,200 lbs for a land-based Mosquito, to provide a (very) thin margin of safety for single engine operations.

Single-engine landings were never really an option.

Rocket Assisted Take-Off Gear (RATOG) was usually needed to get heavily loaded Sea Mosquitoes off the deck.

But true to form, the TR.33 could carry a devastating mix of ordnance, from two 500 lb bombs plus underwing rockets or drop tanks, to four 500 lb bombs, to a pair of 50 gallon drop tanks plus a massive 18 inch torpedo.

And true to type, it had a fully loaded (with drop tanks) range of up to 3,500 miles (5,632 km) at 300 mph, or just under 3,000 miles at 350 mph – making it quite the strike aircraft for its day.

The best of British

In the end, the Sea Mosquito’s remarkable potential was never put to the test. The type equipped 811 Squadron at HMS Peregrine (Ford, Susex) for little more than a year, but never saw frontline service before it was eclipsed by progressively more powerful single-engine aircraft, the lighter de Havilland Sea Hornet, and ultimately, the arrival of carrier-based jets.

However thanks his courage and skill, plus a brave engineer (who flew the first set of trials with him), Eric Brown proved that Geoffrey de Havilland’s incredible Wooden Wonder really could go anywhere and do everything.

A great pilot. And a great British aircraft indeed.

Please do support The People’s Mosquito. (There’s some very cool gear in their Shop.)