Experienced advisor In World War Two, after a stint

Experienced advisor In World War Two, after a stint

Experienced advisor In World War Two, after a stint In World War Two, after a stint

in the Home Guard, Arthur Whitten Brown returned to RAF Training Command, advising on

in the Home Guard, Arthur Whitten Brown returned to RAF Training Command, advising on

in the Home Guard, Arthur in the Home Guard, Arthur Whitten Brown returned to RAF Whitten Brown returned to RAF Training Command, advising on Training Command, advising on

navigation.

navigation.

navigation.navigation.

Freeze a jolly good fellow “The machine was covered with ice, and it continually became necessary to chip

ice off the instruments . . .”

Lt A. Whitten Brown

Vickers Vimy NavigatorVickers Vimy Vickers Vimy Vickers Vimy Vickers Vimy Vickers Vimy NavigatorNavigatorNavigatorVickers Vimy Navigator AircrewAircrew

The offi ce . . . The Vimy’s cockpit is open to the weather – of which there was plenty over the Atlantic. There was nowhere to take refuge, the rest of the fuselage being fi lled with fuel tanks. Calculating position with pencil and maps was a challenge in the howling wind, as was using a sextant for a precision “shot”. The engines were so loud that, even sitting side by side, Brown and Alcock had to communicate by handgestures and notes. The cramped nature of the cockpit is evident in the view below, taken of the transatlantic Vimy as preserved in the Science Museum in London.

tic Vimy as preserved in the Science Museum in London.

ABOVE Arthur Whitten Brown clears snow from the face of the Vimy’s strutmounted fuel overfl ow gauge during the epic transatlantic fl ight of June 14—15, 1919. Illustration by IAN BOTT, www. ianbottillustration.com.

ALCOCK AND Brown’s crossing of the Atlantic in their Vickers Vimy was a major feat of navigation. The long

over-water crossing was a great responsibility for Arthur Whitten Brown, who had been carefully selected for the job by Vickers for his extensive skill and experience as a navigator. The fl ight covered 1,890 miles in 16hr 27min — and proved to be a challenge to even a prepared and experienced navigator like Brown.

navigator like Brown.

time navigation, it took a while for aviators to venture out of sight of land. Over-water fl ying was a challenge, as illustrated during Louis Blériot’s relatively short fl ight across the English Channel in

Just as in the earliest era of maritime navigation, it took a while for aviators to venture out of sight of land. Over-water fl ying was a challenge, as illustrated during Louis Blériot’s relatively short fl ight across the English Channel in 1909 when, on sighting Dover, he found that the breeze had blown him way off course. A World War and a decade later, technology and skills had developed to put the great crossing of the Atlantic within reach. Ships had been travelling across wide open seas for centuries, but many of the navigation

found that the breeze had blown him way off course. A World War and a decade later, technology and skills had developed to put the great crossing of the Atlantic within reach. Ships had been travelling across wide open seas for centuries, but many of the navigation

tools they used were not viable in the air, the speed of aircraft being much greater, and aircraft navigation was not (usually) at sea level.

Not only were modern aids like GPS not available, there were no radio beacons, and air-to-ground wireless (Morse) communication was erratic and of little use for locating a transmitter or receiver. Navigation required a good deal of careful mental calculation, sometimes aided by data tables and logs, and it was very easy to make a mathematical error.

Dead reckoning The primary method Brown expected to use was “dead reckoning”: estimating the current position based upon a previouslydetermined position or “fi x” (exact, known location) and advancing that position based upon known or estimated speeds over elapsed time. With aviation, drift and speed variation owing to wind had to be accounted for, using an equation known as the “wind triangle”, where the relationship between the aircraft’s movement, the air’s movement and the aircraft’s movement over the ground can be defi ned if two factors are

28

AEROPLANE JUNE 2009 AIRCREW

They did it fi rst

“Alcock and Brown showed me the way!”

Charles Lindbergh

vigator vigator vigator vigator vigator vigator vigator

known. As soon as stars, the sun, or a known ground feature was visible, an accurate note of real position could be made, correcting any error from the estimated position. To obtain a fi x with celestial navigation, a sextant was used.

Spoiling the view After take-off from Newfoundland the heavily-laden Vimy climbed slowly eastwards to 1,500ft, but was sandwiched between layers of cloud. Earlier, Brown had written, “Observation of the sun or stars provides a never-failing means of position-fi nding, for it will be seldom indeed that aircraft will be unable to rise above any clouds obscuring the sky”. But this

clouds obscuring the sky”. But this

JAMES KIGHTLY outlines the blend of

technological expertise and sheer toughness required by Arthur Whitten Brown 90 years ago

expectation proved too sanguine, the weather being so poor that the majority of the fl ight was overcast. Luckily, during the night he was able to get a star shot and correct their position and groundspeed (which proved to be a better-thanexpected 122 m.p.h.).

Later, Alcock lost control owing to disorientation in cloud, and other problems affected Brown’s tracking of the fl ight, but when they crossed the coast and saw the radio masts at Clifden, Ireland, they got a fi nal “fi x”. Fortunately for them, they were aiming at a wide target: Europe. Expecting to hit a tiny target such as an island in an ocean was to cost the lives of many aviators.

lives of many aviators.

lives of many aviators.

lives of many aviators.

ABOVE Brown’s sextant and, ABOVE RIGHT, the Vimy’s compass.

ABOVE Brown’s sextant and, ABOVE RIGHT, the Vimy’s compass. ABOVE RIGHT, the Vimy’s compass. ABOVE RIGHT

, the Vimy’s compass.

, the Vimy’s compass.

AEROPLANE JUNE 2009

LEFT One of many magazine advertisements placed to congratulate Alcock and Brown after their pioneering fl ight.

I was there...

Lt Arthur Whitten Brown “. . . over the ocean, his only guides will be the wireless telegraph, or the sun and stars. Wireless telegraphy provides an effi cient and rapid means of locating the positions of an aircraft during a moderately long journey, but its reliability has yet to be proved over greater distances, such as will obtain in the Atlantic fl ight.”

“An hour and a half before we saw land we

had no certain idea

where we were”

Capt John Alcock “On passing Signal Hill [on departure from St John’s, Newfoundland], Lt Brown set out a course for the ocean on 124° compass course and at 3 a.m. from an observation on Polaris and Vega he found he was about 2° south. He then set a course of 110°.”

Major H. E. Wimperis RAF, 1919 “Aircraft are concerned with another ocean — that of the air itself. Its tides are far less easy to predict than the tides in the sea, and are of far, far higher velocity. Its tides are the winds themselves and their intensity may range to 100 m.p.h. or even more. Here are no permanent tide charts to guide the would-be navigator, be his need ever so pressing.”

Capt John Alcock “An hour and a half before we saw land we had no certain idea where we were, but we believed we were at Galway or thereabouts. Our delight in seeing Eashal Island and Turbot Island (5 miles west of Clifden) was great.”

■ Want to know more? See the Database section in this issue of Aeroplane; the original and replica Vimys as listed in the Database survivors’ list, including Alcock & Brown’s original machine, preserved at the Science Museum in London. Shortly before the Atlantic crossing Arthur Whitten Brown wrote a guide to navigation in Flight magazine (April 17 & 24, 1919) which is available through the magazine’s online archive, www.fl ightglobal.com.

29