Today, swords and plowshares. The University of Houston's College of Engineering
presents this series about the machines that make our civilization
run, and the people whose ingenuity created them.
I've talked about the Gargantuan WW-I bombers
built by Germany and Britain -- huge slow biplanes, vulnerable to enemy fighters. But the British
also had an early light bomber, the de Havilland DH.4 -- a two-seat biplane
with a pilot and a rear gunner. It carried 1100 pounds of bombs. Geoffrey de Havilland (actress
Olivia de Havilland's cousin) designed it. Here in America, we built our own version of his DH.4
in huge numbers.
Then, on June 13, 1917, the Germans carried out a daylight bombing of London. Suddenly Britain
knew she must greatly expand her own bombing raids in Germany. So de Havilland offered the
Royal Flying Service his DH.9, an improved version of the DH.4.
It was to fly faster, further, and carry more bombs. Well, I've said before that war is no
friend of invention. War's urgencies get in the way of new ideas, and they surely did in this case.
Great Britain liked the new airplane and put it into production. It was sleek and nice-looking,
with all kinds of new design features. But it immediately proved to be underpowered, slow, and
unable to fly very high. No matter: a war had to be fought so hundreds were flung into combat
anyway. And they performed miserably.
Necessity does that -- it gets ahead of invention. The British expanded production while they
vainly tried new engines and other fixes. By war's end, they were left with thousands of dubious
warplanes. What to do with them?
They sold many off to countries fighting enemies with little or no air power. DH.9s flew with
White Russian forces in the Russian Revolution. They fought in South Africa and the Middle East.
But far more interesting was their civilian use, for they became a kind of laboratory for
peacetime flying.
DH.9s were fitted with every kind of engine. A DH.9, modified for racing, won the 1919 Aerial Derby.
Some were equipped with floats and flew from water. They served well for aerial reconnaissance
and photography. They pioneered air mail service.
In one version, the rear cockpit was removed and replaced with a closed cabin for three passengers,
as well as mail. Others carried two passengers on facing seats in large rear cockpit. DH.9s were
rigged as air ambulances. They were flown from early aircraft carriers. They made popular trainers.
Their wings were equipped with leading edge slots to improve lift. They used propellers with two
blades or four. They used both liquid- and air-cooled engines.
Four thousand DH.9s had been made and, only when war ended, did their invention begin in earnest.
We hardly remember the DH.9 today, but it was still seeing service in the mid-30s. Some were even
resurrected for combat in the Spanish Civil War. The better planes that we do remember benefitted
from all that tinkering. What we couldn't finish in war, we did in peace. We made remarkable
plowshares indeed from this flawed old sword.
I'm John Lienhard at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
P. Cooksley, de Havilland D.H.9 in Action. (color by Don Greer, Illustrations by Joe Sewell) (
Carrollton, TX: Squadron/Signal Publications, Inc., 1996), No. 164.
See also the Wikipedia articles on the Airco DH.9
and Geoffrey de Havilland.
Images: Above, RAF photo of G. de Havilland, Wikipedia image of a DH.9 in Wartime. Below, Australian
DH.9s in war and peace, courtesy of Australian Defense Dept. and Australian National Library, respectively.
The Engines of Our Ingenuity is
Copyright © 1988-2009 by John H.
Lienhard.
