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July 2018
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
north to Selwa at the neck of the Qatar
Peninsula in the south. Several geolo-
gists with sketching boards sat at the
windows and noted every physiographic
detail, from palm orchards to desert
trails, while the camera collected rolls
of film. Together with ground survey
parties, a new map of Arabia was begin-
ning to slowly unfurl inland from the
coastal boundaries.
Using the Fairchild’s photography, the
surveyors established an east to west
base line across the oil concession, from
Jubail on the coast, inland to the Daha-
na sands. Another north-south line ran
at right angles along the track of their
original flight from Jubail to Selwa.
From these a network of aerial triangu-
lation, combined with ground traverses
and astronomical readings from survey
crews, brought the map into accuracy
tolerances. Of the existing maps, only
those of Harry St. John Philby turned
out to be closely reliable or accurate,
with sound latitude fixes by his obser-
vations of Polaris at both upper and
lower culmination. Unfortunately, Phil-
by had lacked for an accurate time piece
and so longitudinal variances were
sometimes as much as 25 miles off.
Another surprise was that flying
conditions in Arabia were somewhat
reversed from that which Kerr had
done previously in the USA. Typically,
in areas of tall structures or vegetation,
aerial photography would be flown
within the hours immediately preceding
and following noon, to minimize ground
shadows. However, the lack of sharp
vertical relief on the windswept sands
of the peninsula, made it difficult to dis-
cern ground elevation changes. Flying
closer to sunrise provided the necessary
shadows for the photogrammetrists to
pin down the ground. Another benefit
to flying first thing in the morning was
the presence of cooler more stable air.
Winds and blowing sand would often
obscure ground sites later in the day.
When the inevitable equipment failures
occurred, the Bedouin, regardless of the
bareness of the region, were always close
at hand. The famous hospitality of the
Figure 8. California-Arabian Standard Oil Co. Saudi Arabia Expedition; Fairchild 71; Saudi
Arabians. National Air and Space Museum Archives. By. Mountain, Joseph D 1902-1970.
Figure 9 California-Arabian Standard Oil Co.
Saudi Arabia Expedition; Fairchild 71; Saudi
Arabians. National Air and Space Museum
Archives. By. Mountain, Joseph D 1902-1970.
to hold twin cameras. A removable
window on each door was contrived
so as to mount the camera for oblique
photography. In order to land and take
off safely on the soft terrain, the plane
was equipped with the largest diameter
tires available (36”x18”). The inclusion
of an extra fuel tank further reduced
the interior carrying capacity to only
four passengers, but gave the Fairchild
a cruising radius of 350 nautical miles.
The next difficulty faced by the aerial
photography crew was finding a film
that would withstand both the heat
and high humidity found along the
Gulf Coast of Arabia. Working directly
with Eastman Kodak specialists, Kerr
helped test aerial films that could be de-
veloped in water with temperatures as
high as 120 degree (F). This was done
using a unique film with a potassium
chrom alum base. However, even with
these contrivances a whole distillation
unit was needed to purify the water for
the developer as the mineral content
of the native wells was an unknown
factor.
The plane was finally shipped on the
American Export Lines S.S. Exodi-
orda on February 6, 1934; 23 days
later it was unloaded at the harbor in
Alexandria, Egypt. Through several
sandstorms and missed rendezvous
with refuel stations, in Gaza and Iraq,
Kerr and his mechanic/co-pilot Charley
Rocheville finally landed in the oasis
of Al-Hasa. Unfortunately, due to the
brewing war with the Imam of Yemen
(the Saudis invaded northern Yemen in
May 1934) the pair were unable to begin
their aerial mapping until March 30
th
.
Starting with the coast and working
their way inland, Kerr and Rocheville
flew in straight parallel lines, six-miles
apart, from Ras Tanura sandspit in the
