JtTIY 27. 1939 0B&* 77 ' Flight" photograph. TRAINER DE LUXE The Miles Master I Described : High Performance with Comparatively Low Power : All-wooden Construction IRST deliveries are now being made to the R.A.F. of The oval-section plywood-covered fuselage is of fine aero­ the Miles Master I two-seater advanced training dynamic form and of semi-monocoque construction with a F monoplanes built by Phillips and Powis Aircraft, large cut-out for the cockpits. The tail unit is of conven­ Ltd., at their Reading works. Fitted with the tional cantilever design, the tailplane being mounted on top specially developed Rolls-Royce Kestrel XXX '' train­ of the rear portion of the fuselage, in which position it has ing" engine, the Master has a top speed of 264 m.p.h., a wide attachment base and facilitates recovery from a and will enable pupils to "get on a few 'G,'" and spin. generally to accustom themselves to the handling charac­ Between the tandem cockpits (the pupil occupies the teristics of contemporary monoplane fighting aircraft, front seat) is a sturdy metal former which, while not pro­ apart from providing for front-gun practice and other jecting beyond the fuselage, offers protection for the crew branches of instructional flying. in the event of a nose-over. The Master I may be considered as a development of The plywood-covered wing is of N.A.C.A. 230 section the original Miles Kestrel Trainer, which was capable of and is very deep at the root, though the top spar boom is 295 m.p.h. or more with a Rolls-Royce Kestrel XVI engine continued across the fuselage without interfering with ihe of 745 maximum h.p. Technically, the machine is in­ pilot's use of the rudder bar. The two spars are of normal teresting more for its aerodynamic features than for its box construction, but are specially shaped to give the structure, which is, in fact, quite orthodox. "inverted gull" centre section which is characteristic of There is no doubt that, in the Master, Service trainees will have "a real aeroplane." The top speed of over 260 m.p.h. cai* be credited on examining this view. 78 jfe&n JULY 27, 1939 MILES MASTER I Rolls Royce Kestrel XXX Engine DIMENSIONS AND AREAS Length ... 30ft. 8m. Minimum height (tail down) ... ... 10ft. Span ... 3SJt- Track ... ... ... 12ft. 3£m. Airscrew diameter ... 10ft. Wing area ... 217 sq. ft. Aileron area ... 16.72 sq.ft. WEIGHTS Tare weight ... 4,1601b. Fuel (70 gal.) ... 5251b. Oil (5 gal.) ... ... 451b. Pilot, pupil and parachutes ... 4001b. Equipment ... 1451b. Max. permissible weight ... ...5,5001b. PERFORMANCE Top speed at sea level ... ... 209 m.p.h. Top speed at 10,000ft. ... ... 244 m.p.h. Top speed at 15,000ft. ... ... 264m.p.h. Cruising speed (two-thirds power at 15,00trft.) ... 230m.p.h. Range at 216 m.p.h. (allowing SB gal. of petrol for ground running, climb and descent) ... 440 miles Climb to 15,000ft. ... lOmin. Service ceiling ... 28,000ft. Take-off run (still air) ... ... 293 yd. Landing run (still air, using flaps and brakes)... ... 320 vd. Landing speed ... 67 m.p.h. Kestrel V, but in comparison is derated for climbing and level flight to provide the longer overhaul life required by a training aircraft, the rated boost being reduced to +|Ib./sq. in. A high take-off power is, however, retained. The actual figures are: rated power, 550 h.p. at 2,400 r.p.m. at 11,750ft.; maxi­ mum power, 600 h.p. at 2,750 r.p.m. at 14,500ft.; take-off power, 720 h.p. at +5lb. boost at 2,750 r.p.m. An ejector- the Master. This feature, of course, makes for higher produc­ type exhaust system is used. tion costs, but it is felt that it is justified on the grounds of Hand-starting gear is fitted as standard, and auxiliary drives performance. The depth of the centre section permits stowage are provided for a vacuum pump for driving the gyroscopic of the fuel tanks and the undercarriage in its retracted position instruments; a constant-speed unit driven from a dual-drive The centre section houses a free-firing machine gun and para­ unit at the front of the reduction gear casing; a Lockheed chute flares are carried in the outer panels. hydraulic pump for undercarriage and flaps; a high-pressure Hydraulically operated split trailing-edge flaps extend under air compressor; and a 500-watt Rotax electric generator. the fuselage. These may be depressed to an angle of about The airscrew shaft of the Kestrel XXX will accommodate 25 deg. for take-off and 90 deg. for landing. Their position is either a Rotol or De Havilland constant-speed airscrew. For recorded by an electrical indicator on the instrument panel. the Rotol, which is standardised on the Master, the oil supply All electrical leads are housed in ducts. passes through an external muff type of feed located in the High-tensile steel, backed up with forgings and magnesium- housing at the front of the reduction gear casing. alloy castings, is used for the engine mounting attachment Under the fuselage, between the spars, is a low-drag cooling plates. The Rolls-Royce Kestrel XXX is mounted with Ferodo duct for the water and oil systems. This has a variable outlet packings under the bearer feet, and the steel tubular mounting controlled from the front cockpit. is designed to facilitate engine removal. The complete instal­ The main fuel tanks—which, as already stated, are carried lation (power unit, vacuum pump and relief valve, hydraulic in the wing roots—are two in number and hold 36 gallons each. pump and constant-speed unit) may be taken out of the air­ They are readily removable through doors in the lower surfaces frame by removing four main bolts and disconnecting the of the wing. The oil tank is mounted behind the fireproof various leads through the bulkhead. bulkhead and has a partial circulator, the shell of which may be The Kestrel XXX engine is essentially similar to the replaced to give a different rate of warming-up to suit local r .... 1 m Wtfg f^VT^Ifc^^,. 9 /•"-'•' ••:'&• i-JB Hii|iH^*'''',.-;-i4%iJ V* - mm^mmWrnwaSmm. .. Mm, "Flight" pkotognipit Showing how, for landing, the instructor can raise himself to obtain a good view. The raising of the windscreen is automatic. JULY 27, 1939 Sto®%m 79 Mr. H. W. C. Skrnner, chief test pilot, does a "straight and level" above the clouds on a production Master. conditions. The water header tank is mounted at the front of the engine above the reduction gear housing. The retractable under­ carriage is of particular interest in that the wheels twist through 90 deg. during retraction into the centre section. There are two independent units which are operated by the Lockheed hydraulic cir­ cuit, though emergency pipe lines and a hand pump are fitted in case of failure of the main pump. A position indi cator is interconnected with the ignition switch and the throttle panels are also fitted to permit rapid exit from either cockpit control Notwithstanding the fact that the electrical indicator on either side should the machine nose-over on landing. The is fitted with duplicate bulbs a mechanical indicator is also front windscreen is of moulded Perspex, and is fitted with a fitted. The brakes are hydraulically operated, and the wheels Triplex panel in the region of the reflector gun sight to give an and tyres can be Palmers or Dunlops. A cut-out is provided optically perfect view of the target. For bad-weather flying in the instructor s cockpit to render the pupil's brake controls two small panels in the screen may be opened. The remarks inoperative. concerning the emergency exits and the opening of the front As the Master is an advanced Service trainer much of the windows apply equally to the rear windows. Provision is interest centres on the cockpits which are both commodious and made for sunblinds under the top portion of the cabin roof. comfortable. The front windows of the enclosure slide upwards Of special interest are the arrangements made to ensure that on channels round the port side, there being a fixed hinge on the landing view from the rear seat is comparable with that the starboard side. For use in the air there are emergency catches on both sides, while very large quickly detachable HINGED WINDOWS A.S.I. 9- Oil pressure. Artificial horizon. 10. Fuel pressure. Rate-of-dimb. zi Oil temperature. Altimeter. 12. Fuel gauges. The "business quarters" of the Master, our latest Service Direction gyro. IB­ Radiator temperature. trainer. A key to the instruments, which are numbered in Turn indicator. M- Brake pressure. the drawing, appears on the right. R.P.M. I•oS. Hydraulic pressure. Boost 16. Landing-light switch JULY 27, 1939 8o $J»©c w (Left) Undercarriage and landing light installa­ tion. The wheels turn 90° during retraction. (Below) The complete wing of a Master show­ ing the formation of the centre gulled portion. Flight " photographs. A typical control run on the Master, showing the application of the neat rubber-tyred ball races. from the front. A vertical adjustment of the seat of i2in. is allowed instead of the normal 4m., bringing the occupant's head outside the normal fairing line of the cabin roof and giving him a good view over the leading edge. Whilst in this position he is protected by a windscreen which is automatically raised out of the cabin The adjustment of the rudder bar may be made simultaneously with the change in position of the seats.