Harrier Jump Jet – Vertical Flight

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The Harrier Jump Jet is one of the most extraordinary planes ever built, it can hover in mid-air, and doesn’t need a runway. This British design is a helicopter and a
high performance jet all in one. CLIVE SOFFE: Flying a Harrier is awesome, the Harrier to me is the best aircraft in the Royal Air Force, and because it does so
many different things, the Harrier is one of those aircraft where you’re constantly saying well I think I can do it a bit better. The Harrier cruises at 500 knots, it’s one
of the world’s most manoeuvrable jets. As a tactical bomber it has supreme performance on low level raids. The Harrier’s greatest strength is that
it can land anywhere. Small landing sites can be set up near the
front line, the aircraft hidden in a camouflage shelter. Ground crews can rearm and refuel in just
half an hour. A vertical take-off would use so much power that the Harrier could not carry a full load of bombs. Using a rolling take-off a fully laden Harrier needs only 600 feet of runway. Conventional military jets need up to 9000. CLIVE SOFFE: The Harrier is built round this single huge engine, the Pegasus, which employs a unique system of nozzles. 4 nozzles moving
simultaneously, if they’re pointing backwards, that’s normal conventional flight. If we move the nozzles down, we can hover our aircraft by ducting some of the thrust of the engine downwards. When it’s hovering the Harrier’s conventional flying surfaces don’t control the plane, that’s the job for smaller thrust nozzles,
called puffer ducts. CLIVE SOFFE: These are the puffer ducts. 4 puffer ducts, one on either wing, one on the nose, and one on the tail. Duct some of the thrust from the engine to actually push up or push down, so I can now use my controls in the conventional sense, but I can now maintain a precise hover. The pilot uses his stick to operate both the conventional control surfaces and the puffer ducts, at the same time. The Harrier’s unique technology makes it
one of the hardest planes to fly. Only the very best get the chance to fly it. CLIVE SOFFE: We take the top guys who come through training, and then it’s our job to get those guys through the Harrier conversion course. Now obviously it’s an extremely hard course and unfortunately not everybody
can actually make the grade. In training Harrier pilots use a special two-seater, the student sits in the front, the instructor has duel controls at the back. CLIVE SOFFE: The Harrier is very, very unforgiving if a guy makes a poor error of judgement. If he puts a wrong flap setting when he’s
on a strip and he tries to get airborne, he will die. The instructor in the back of the
aircraft, he’s working pretty hard to make sure he’s matching what the student is doing. We don’t want to see a student get a mistake between the throttle and the nozzle. Stage one of vertical flight training, students repeat to perfection short rolling landings and take-offs on difficult terrain. CLIVE SOFFE: The critical point for us is
120 knots to 30 knots, and what we have to try and do is teach a student to get through this area, to be able to get to the hover. Learning to hover is the hardest stage of
all. CLIVE SOFFE: When you first start flying the Harrier, when you hover it, it’s almost as if you’re on a knife edge, and you’re afraid to move the stick or the throttle in case you fall off that knife edge. DAMIAN KILLEEN: It’s something that you’ve never done before, it’s like no other aspect of flying you’re doing. The concentration level is about as high as it possibly can be, because you know if you do something wrong, the jet is liable to bite you and hit the ground like a brick. It concentrates the mind a heck of a lot. Vertical take-off and landing aircraft were
developed so planes could take-off if their runways were destroyed. During World War II the German Luftwaffe attached disposable rockets to their planes to reduce take-off distance. In the 50s and 60s engineers worked on over 30 different prototypes. Firing planes off the back of trucks, known as zero length launch, was a surprising success. The problem was they still needed a runway to land. The weird looking tail-sitters were developed with both propellers and jet engines. The transition from vertical flight to normal flight was hard, and landing was nearly impossible. The pilot of this Ryan Vertijet had to literally hook his plane on a stand. In 1954 Rolls-Royce demonstrated a new concept, this prototype became known as the Flying Bedstead. Vertical flight came from the thrust of two
jet engines directed down through adjustable nozzles. The principle was applied to the first British prototype, the Short SC1. This had 5 small jet engines, 4 for vertical
flight, and 1 for horizontal. But the major breakthrough came with the development of this engine, the Rolls-Royce Pegasus was the first single engine powerful enough to lift a full size military plane vertically. Today the Harrier is the ideal warplane for
the US Marines. On their amphibious assault ships 4 Harriers and 30 choppers use a flight deck less than a quarter of the size of an aircraft carriers. MAJOR BILL TUCKER: We have no resting gear or catapult gear, and we just rely on the Harrier’s ability to rotate the nozzles
on a short take-off for launch, and a vertical landing for recovery. The nozzles will be aft at the beginning of the take-off roll, until you hit he end of the ship where you’ll be going somewhere between 90 and 110 knots. As you hit the end of the deck you will move the nozzle lever down to 55 degrees and then airplane will fly away. Using vertical landings Harriers can operate in far worse conditions than conventional jets. In combat they provide vital support for the ground troops during amphibious landings. Each assault ship can put thousands of troops ashore by helicopter and landing craft. Ahead of them the Harriers take out key enemy positions.

 

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