Houston Everest Flight Articles
Chronology Of The Everest Flights
The Westland Wallace
The Houston Westland Aircraft
Everest Bristol Pegasus S.3
The Everest Flight Cameras
Pre Expedition Proving Tests
Departing For Everest
Members Of The Expedition
Everest Conquered
The Second Flight
The Everest Year
The Times Luncheon

The Houston Westland G-ACAZ

FOR MOUNTAINEERING IN COMFORT: Three views of the" Houston-Westland." (FLIGHT 2nd Feb 1933)

The Westland P.V.3 was designed to meet the requirements of Army cooperation and Fleet Air Arm cooperation and Fleet Air Arm work, and is of the class known as a General Purpose aircraft. This necessarily meant that the machine was designed for carrying heavy loads. Consequently the wing area is com paratively large (500 sq.ft.) to avoid too great wing loading, and this in turn renders the machine suitable when fitted with a fully supercharged engine, for work at considerable height. For the forthcoming Houston-Mount Everest flight a high ceiling was the first consideration, and when it came to selecting an available aircraft type the choice fell on the Westland P.V.3. In its military form the machine was fitted with the Bristol Jupiter X.FA engine, but for the flight over Mount Everest, which is scheduled to take place some time in March, one of th e new Bristol Pegasus" engines, type S.3, has been fitted. This engine is fully supercharged, has a propeller reduction gear ratio of 0.5 to 1, and at its rated altitude of 11,000 ft. develops a normal power of 525 b.h.p, at 2,000 r.p.m., and a maximum power of 570 b.h.p. at 2,300 r.p.m. For taking off at sea level the maximum power permissible for 3 min. at normal r.p.m. is 500 b.h.p.

Fundamentally the Westland P.V.3 is an all metal two-bay tractor biplane, of orthodox design in the matter of general layout, but characterised by wings of high aspect ratio to obtain the lowest possible induced drag during climb. The undercarriage is of very wide track (12 ft. 10 in.), as the machine was originally designed with a view to being capable of carrying a 1,000 lb. torpedo. Duralumin is the material used in the construction of the wing structure, and the wing arrangement includes a top centre lower plane. It should be noted that the " P.V.3 " differs from most torpedo planes in that there are no sloping struts running from the inner interplane struts to the fuselage. The wings are arranged to be folded, the hinges and locking devices occurring at the points of attachment of undercarriage to lower wing. The inner interplane struts are of " N " formation and made of streamline steel tube, while the outer interplane struts are built-up duralumin construction with " Alpax " end castings. Handley-Page automatic wing tip slots are fitted in the upper wing, and lower as well as upper wing is fitted with Frise-balance ailerons. The fuselage of the "P.V.3" is of usual Westland type of construction, in which the tubular members employed are jointed together by bolting Square-section tube (with rounded corners) is used almost throughout.

The engine is carried on a steel tube structure incorporating " Silentbloc " suspension In its military form the " P.V.3 " carries a large equipment in the form of front and rear guns, bombs or torpedo. Oxygen equipment, camera, gun, wireless, photographic equipment, gear for picking up messages, all according to the particular function for which the machine is being used. For the Houston-Mount Everest flight the " P.V.3 .. was selected on account of its high ceiling (more than 34,000 ft.) and for the large space in the rear cockpit, which gives the observer ample room to move about during his work of using the fixed camera and the hand-held cine camera.

Lord Clydesdale and Lt, Col. Blacker in altitude kit. (FLIGHT Feb 1933)

Some of the photographs illustrate the modifications which have been made to the machine to make it suitable for the Everest flight, and the special equipment which the machine will be called upon to carry. From the photographs it will be noted that the aft cockpit has been entirely covered in.

The hinged door in the roof of the observer's cockpit is arranged to fold inwards, so that if the observer should at any time during the flight want to get his head out in the open, the doors will not 'flap about in the slipstream. The circular windows in the roof door can be seen in one of the photographs.

SOME OF THE EQUIPMENT: With the fuselage panel removed the interior can be inspected. Note the Williamson camera in its electrically-heated jacket.

The crew, which during the actual flight over Mount Everest will consist of the Marquis of Clydesdale (pilot) and Lt. Col. Blacker (observer and photographer), wears electrically-heated clothes and gloves, and the cockpits are further protected against cold by three-ply walls added inside the fuselage structure proper. Particular care has been taken in the design of the flight controls, to ensure that uneven rates of contraction shall not render them inoperative at great heights.

Left - THE CREW READY FOR A TEST FLIGHT: The Marquis of Clydesdale will pilot the machine, and Lt, Col. Blacker will act as observer and photographer. Right -  THOSE RESPONSIBLE FOR THE FLYING EQUIPMENT: Left to right, Mr. A. Davenport, Chief Designer ; Mr. H. J. Penrose, Test Pilot, and Mr. R. A. Bruce, Managing Director of Westlands. (FLIGHT Photo)

As used on the Everest flight, the" P.V.3," or, as it has now become, the " Houston-Westland," has a tare weight of 3,580 lb. The load carried will consist of : Crew and heated clothing, etc ., 380 lb ; oxygen , cameras, etc., 206 lb.fuel and oil, 704 lb. This gives a gross weight of 4,870 lb.

The "Houston-Westland" has now been shipped to India (Feb 1933), and work is proceeding on a second machine to act as ,second' string." This is of the Westland "Wallace" type, as supplied to the British Royal Air Force. Being of the General Purpose" class of aircraft, the "Wallace " had similar advantages for the Everest flight as the "P.V.3 ," and it is now being modified for the work. The Engine of this machine is also a 'Bristol Pegasus
S.3.

TACKLING EVEREST: The dot-dash curve shows flight test made at Yeovil, while the other two are estimated,
the upper being a normal climb to height curve while the lower is the type of approach it is intended to use.

The chart illustrated above is of considerable interest, and merits a close study. It will be seen that on it is drawn a silhouette of Mount Everest. and three separate curves. I he dot -dash curve shows the results of a flight test made by Mr. Penrose at Yeovil, but plotted on the assumption that the machine was flying from its base III the same direction the whole time. This was not, of course. actually the case. The other two curves show two methods of getting over the top of Mount Everest. Both represent estimates made before the test flight was carried out. The upper curve shows the re suit which would be obtained by a normal climb to height. while the lower curve represents the actual method which it is proposed to use in order to get close enough to the mountains to be able to take photographs on the way up. It will be seen that after reaching an altitude of 11.000 ft. which is the rated altitude of the Bristol "Pegasus" S.3 engine, the machine will be flown level towards the mountains, and then when a certain point has been reached the climb will be resumed until the machine has crossed the summit of Everest.