AP 118 · No. 10 Section II · Aircraft Plate 224 / 269

Plate 224 of 269 · Early jet age · Slender-delta low-speed research aircraft

Handley Page HP.115

HP.115, XP841, painted as XP841, the only Handley Page HP.115 built, displayed in the Leading Edge hall of the Fleet Air Arm Museum, Yeovilton, beside the BAC 221 and Concorde 002: the slender-delta research aircraft built to Specification ER.197D to explore the low-speed handling of the wing chosen for Concorde, first flown at RAE Bedford on 17 August 1961 and retired in 1974, with a 75-degree swept delta wing with sharp, interchangeable leading edges, a slim fuselage with the cockpit well forward under a small canopy, one Bristol Siddeley Viper turbojet in a pod above the rear fuselage at the root of a large swept fin, elevons and a fixed tricycle undercarriage borrowed from the Jet Provost, shown sitting slightly nose-up on its wheels with its nose boom fitted: bare metal overall with a duller silver wing, a black anti-glare panel over the nose, black photo-calibration discs with a white cross on the nose, engine pod and fin, red ‘AERO’ over ‘FLIGHT’ with ‘R.A.E BEDFORD’ in black and the red RAE triangle badge on the nose, ‘HP’ over ‘115’ near the nose cap, a Type D roundel and black ‘XP841’ on the rear fuselage, a red, white and blue fin flash and a red intake blank (shape from the airwar.ru three-view scaled to the published 15.33 m length, cross-checked against J.D. McHard’s 1961 plan and the published span and wing area; paint and markings following photographs of XP841 in the museum from 1984 to 2020; no wing roundels are painted, since no photograph of the museum airframe shows them); it stands for the research one-offs in the gazetteer’s museums, from the Hunting H.126 and the Short SB.4 Sherpa to the Hawker P.1052 and the Saunders-Roe SR.53.

3D model

Turn it over

A procedural model built in Blender from published dimensions, drawings and photographs, painted as XP841, the only Handley Page HP.115 built, displayed in the Leading Edge hall of the Fleet Air Arm Museum, Yeovilton, beside the BAC 221 and Concorde 002: the slender-delta research aircraft built to Specification ER.197D to explore the low-speed handling of the wing chosen for Concorde, first flown at RAE Bedford on 17 August 1961 and retired in 1974, with a 75-degree swept delta wing with sharp, interchangeable leading edges, a slim fuselage with the cockpit well forward under a small canopy, one Bristol Siddeley Viper turbojet in a pod above the rear fuselage at the root of a large swept fin, elevons and a fixed tricycle undercarriage borrowed from the Jet Provost, shown sitting slightly nose-up on its wheels with its nose boom fitted: bare metal overall with a duller silver wing, a black anti-glare panel over the nose, black photo-calibration discs with a white cross on the nose, engine pod and fin, red ‘AERO’ over ‘FLIGHT’ with ‘R.A.E BEDFORD’ in black and the red RAE triangle badge on the nose, ‘HP’ over ‘115’ near the nose cap, a Type D roundel and black ‘XP841’ on the rear fuselage, a red, white and blue fin flash and a red intake blank (shape from the airwar.ru three-view scaled to the published 15.33 m length, cross-checked against J.D. McHard’s 1961 plan and the published span and wing area; paint and markings following photographs of XP841 in the museum from 1984 to 2020; no wing roundels are painted, since no photograph of the museum airframe shows them); it stands for the research one-offs in the gazetteer’s museums, from the Hunting H.126 and the Short SB.4 Sherpa to the Hawker P.1052 and the Saunders-Roe SR.53. Drag to orbit, scroll or pinch to zoom · download .glb (854 KB)

Data plate

Specification

First flight, number built and top speed are for the whole family (HP.115, Hunting H.126, Short SB.4 Sherpa, Hawker P.1052 & P.1121, Saunders-Roe SR.53); engine, crew and dimensions are for the HP.115, XP841 modelled here.

History

The HP.115

In the late 1950s British planning for a supersonic airliner settled on a slender delta wing: a long, narrow, sharply swept wing that would cruise efficiently at twice the speed of sound. Dietrich Küchemann and Johanna Weber at the Royal Aircraft Establishment had shown that such a wing, with sharp leading edges, rolls the air into two strong vortices over its upper surface that keep it lifting at high angles of attack. What nobody knew was how it would behave at the other end of the speed range, in the approach and landing, where a passenger aircraft has to be safe and easy to fly.

To find out, the Ministry of Supply ordered a small, cheap research aircraft from Handley Page under Specification ER.197D. The HP.115 had a 75-degree swept delta wing of only 20 ft span on a slim fuselage, with the pilot sitting well forward in an ejection seat, a single Bristol Siddeley Viper turbojet in a pod above the rear fuselage, a large swept fin and a fixed tricycle undercarriage taken from the Hunting Jet Provost. Its leading edges were made of wood and could be changed, so that different shapes could be tried in flight. Squadron Leader Jack Henderson first flew it from RAE Bedford on 17 August 1961.

The HP.115 proved that a slender delta was perfectly manageable at low speed. It flew comfortably at well under 100 mph, with no sudden stall, and its handling at high angles of attack, in rolls and in sideslips gave the designers of Concorde the confidence and data they needed; its high-speed partner was the BAC 221, a Fairey Delta 2 rebuilt with an ogee wing. The HP.115 went on flying with the RAE’s Aero Flight on research into vortex flow and handling long after Concorde itself had flown, and made its last flight on 1 February 1974. Only one was built.

This airframe

HP.115 XP841

XP841The airframe modelled

XP841 was the only HP.115 built. It flew with the Royal Aircraft Establishment at Bedford for more than twelve years, latterly with its Aero Flight, and after its last flight in 1974 it went to the museum at RAF Colerne and then to the RAF Museum at Cosford, before joining the Fleet Air Arm Museum at Yeovilton, where it stands in the Leading Edge hall beside the BAC 221 and Concorde 002, the aircraft it helped to design. The model shows it as displayed there, sitting slightly nose-up on its fixed undercarriage with its nose boom fitted: bare metal overall with a duller silver wing, a black anti-glare panel over the nose, black photo-calibration discs with a white cross on the nose, engine pod and fin, red ‘AERO’ over ‘FLIGHT’ with ‘R.A.E BEDFORD’ in black and the red RAE triangle badge on the nose, ‘HP’ over ‘115’ near the nose cap, a Type D roundel and black ‘XP841’ on the rear fuselage, a red, white and blue fin flash and a red intake blank. Photographs from its flying days show roundels on the wings, but none of the museum airframe shows them, so none are painted. The shape follows the airwar.ru three-view, scaled to the published 15.33 m length and checked against J.D. McHard’s 1961 plan and the published span and wing area; the paint follows photographs of XP841 in the museum from 1984 to 2020. The model stands for all the research one-offs in the gazetteer’s museums, from the Hunting H.126 jet-flap aircraft and the Short SB.4 Sherpa to the Hawker P.1052 and the Saunders-Roe SR.53 rocket fighter.

See it at Fleet Air Arm Museum

Where to see one

In the gazetteer

The gazetteer records the HP.115 in 4 UK collections. The airframe modelled here is marked.

Every airframe and serial All 269 plates

Profiles and models are procedural interpretations built in Blender from published dimensions, three-view drawings and photographs of each airframe. Treat the museum aircraft as the reference.