Benutzer:Frank Murmann/Spielwiese
| Pratt & Whitney | |
|---|---|
 Vorserienexemplar des J57 | |
| J57 | |
| Produktionszeitraum: | 1952–1965 |
| Hersteller: | Pratt & Whitney |
| Typ: | Turbojet |
| Entwicklungsland: |  Vereinigte Staaten
|
| Erstlauf: | 1952 |
| Stückzahl: | 21170 |
| Länge: | 4,65 m |
| Durchmesser: | 1,04 m |
| Rotordurchmesser: | 0,99 m |
| Trockengewicht: | 1990 kg |
| Schub: | 38,7 kN |
| Verdichterkompression: | 11,6:1 |
| Nebenstromverhältnis: | ??? |
| Nachbrenner: | nein |
| Vorgänger: | J56 |
| Nachfolger: | J58 |
Konstruktion
[Bearbeiten | Quelltext bearbeiten]Die Miles Master war ein von einem Kolbenmotor angetriebener, freitragender Tiefdecker in Tandemkonfiguration.[1] Die ersten Exemplare waren mit einem Kestrel XXX mit einer Nennleistung von 745 PS (548 kW). Mit diesem Triebwerk erreichte das Flugzeug eine Höchstgeschwindigkeit von 296 mph (476 km/h),[2] womit die Master die gleichen Geschwindigkeiten wie die einsitzigen Doppeldecker dieser Zeit.[1]
Die Knickflügel der Master waren ein
The inverted gull-shaped wing of the Master was a major distinguishing factor of the aircraft and was adopted, despite higher production costs, due to its performance benefits, permitting the stowage of both the retractable undercarriage and fuel tanks; aside from this shaping, the wing's design largely conformed with traditional approaches.[3][4] It features hydraulically-actuated split flaps along its trailing edge, their position being indicated electronically on the cockpit's instrumentation planel. The wing's center-section also accommodates a machine gun.[5]
While the Master had incorporated relatively advanced aerodynamic characteristics (intended to mimic frontline fighters) for a contemporary trainer aircraft, it used a conventional structure, comprising an oval-section fuselage covered by a plywood skin, featuring a semi-monocoque approach.[6] Forward of the tandem cockpits, the nose is strengthened by a metal former that provides protection against nose-overs, a common occurrence amongst trainee pilots when flying aircraft outfitted with a 'taildragger' undercarriage. The tail section had an orthodox cantilever structure, the tailplane being mounted directly on top of the fuselage; according to Flight, the tailplane's aerodynamics were designed to facilitate easy spin recovery.[6] The Kestrel engine is mounted on tubular steel bearings which was designed to facilitate engine removal for ease of maintenance via the undoing of only four main bolts along with the connecting leads. Further maintenance savings were made via the engine's derating, allowing for a longer interval between overhauls.[5]
The Master was furnished with a constant-speed propeller, which was interchangeable between Rotol and de Havilland units.[5] The Kestrel engine of early-built aircraft incorporated various auxiliary drives to power both vacuum and hydraulic pumps, along with an air compressor and a 500-watt electrical generator. Cooling for the water and oil systems was provided via a duct running underneath the fuselage.[5] Fuel was housed in a pair of fuel tanks, each containing up to 36 gallons, accommodated within the wings; the oil tank is mounted behind a fireproof bulkhead while the water tank is mounted in front of the engine. The retractable undercarriage is operated via two separate hydraulic systems along with a hand-pump as backup; the brakes are also hydraulically-actuated.[7]
The cockpit of the Master was designed was considerable attention to best facilitate its use as a trainer aircraft, including for use of use and comfort.[8] The positions of the two flying crew, the student in front and the instructor behind, was staggered; the rear position is 12-inches higher to provide the instructor with greater visibility.[9] Mid-flight, an instructor was able to disconnect several of the student pilot's controls, such as the brakes, using various cut-outs provided. The forward windscreen is composed of molded Perspex and is furnished with a reflector-type gun sight, providing an optically-perfect view of a target.[8] Two small panels can be opened to aid visibility while flying in poor weather conditions, sun blinds are also incorporated. Catches on either side of the sliding canopy allow for the panels to be rapidly detached, facilitating faster bailing-out during an emergency.[8] Other emergency equipment included a Graviner fire extinguisher mounted behind the rear seat and emergency hydraulic controls set into the floor on the cockpit.[10]
- ↑ a b Referenzfehler: Ungültiges
<ref>-Tag; kein Text angegeben für Einzelnachweis mit dem Namen flight milestones. - ↑ Referenzfehler: Ungültiges
<ref>-Tag; kein Text angegeben für Einzelnachweis mit dem Namen Amos aeroAug80 p413-4. - ↑ Flight, 27 July 1939. pp. 77-78.
- ↑ "Aircraft Types and their Characteristics: Miles Master III." Flight, 22 October 1942. p. a.
- ↑ a b c d Flight, 27 July 1939. p. 78.
- ↑ a b Referenzfehler: Ungültiges
<ref>-Tag; kein Text angegeben für Einzelnachweis mit dem Namen flight 77. - ↑ Flight, 27 July 1939. pp. 78-79.
- ↑ a b c Flight, 27 July 1939. p. 79.
- ↑ Flight, 27 July 1939. pp. 79-80.
- ↑ Flight, 27 July 1939. p. 80.