Handley Page Hendon (HP.25)

History

Part of Handley Page's work in the early 1920s to meet the 1920's Standing Fleet Aviation (FAA) requirement for modern carrier-based torpedo bombers was "Hendon". The two-seat torpedo biplane was built alongside the single-seat "Hanley" of similar form and function, both of which would eventually be replaced by the Blackburn "Dart" (detailed elsewhere on this page).

Hendon completed six prototypes and flew them in 1924, but these aircraft ended their days as test aircraft for various wing surface controls and evaluation of carrier operations.

The aircraft displayed many qualities of that era: upper and lower biplane wing configuration, open-air cockpit and fixed tail-tow landing gear. The wings are multiple rows of parallel struts, not stacked. As usual, the engine is located in the nose, driving the two-bladed propeller. The cockpit is located near the midship, and the pilot's visibility is generally poor (the gunner is just behind). The fuselage has plate sides and tapers towards the stern, with a rudder mounted on the empennage.

The landing gear consists of two-wheeled components under the front mass of the aircraft, with a simple tail skid under the tail.

FAA authorities saw enough value in Hendon to order it as a test aircraft through a contract dated 27 November 1923 - covering a total of six aircraft. Hanley designed this two-seater based on Hanley's last form, the Hanley III. Hanley III, the third of three iterations to emerge from the Hanley program, finally addresses control issues in the design, while employing full-span leading edge slots for the low-altitude, low-speed handling required for carrier operations is critical.

Specification 25/23 was created for a new aircraft then called "Typ Ta" (later renamed "HP.25").

The first flight of the

Hendon prototype was recorded on July 7, 1924, with the entire batch undergoing further testing before the end of the year. When all-war loads were added, some modifications were made to the design, resulting in the wing main aircraft being moved slightly aft to accommodate the heavier loads on the tail.

Completed three different variants of Hendon: Hendon I, Hendon II and Hendon III. The Hendon II brand is three redesigned Hendon I aircraft with improved slotted gearing, while the Hendon III is a one-off conversion of the slotted flap Hendon II model.

The basic approach to the design borrowed heavily from Hanley, except for the slightly elongated fuselage to accommodate a second crew member - hence the use of a tandem seating arrangement. Dimensions include a barrel length of 34.5 feet, a wingspan of 46 feet, and a height of 13.7 feet. Curb weight reaches 4,350 lbs and maximum takeoff weight (MTOW) reaches 7,000 lbs.

Power came from a Napier Lion IIB 12-cylinder, 450-horsepower, water-cooledthe same engine used in earlier Hanley and rival Dart aircraftto drive a two-blade wood propeller. Performance specs include a top speed of 110 mph and a service ceiling of up to 9,500 feet.

Standard armament is a nose-mounted .303 Vickers machine gun mounted on a fixed forward-firing mount, synchronised by rotating propeller blades, and a .303 Lewis machine gun mounted in the rear cockpit On the training stand. The bomb load is a single 18" (457 mm) aerial torpedo or 2 x 230 lb drop bombs.

Specification

Basic

Production

Roles

Dimensions

Weight

Performance

Performance

Armor

Changes