FREQUENTLY ASKED QUESTIONS

How fast does it go?

The King Air B200 has a maximum speed of 259 knots or Mach 0.52. One ‘knot’ is ‘one nautical mile per hour’, and since a nautical mile is 1.15 statute miles, 259 knots is equivalent to 298 mph. On take-off, at light weight, the King Air B200 accelerates from 0 to 100 mph in about 12 seconds.

How much power?

Each of the Pratt and Whitney PT6A-42 turboprop engines produces 850 horsepower. With a total of 1700 horsepower and a typical display weight of 4.5 tonnes (about 10,000 lbs), the King Air B200’s power to weight ratio is 378 horsepower per tonne, which is more than most high performance sports cars.

What is a turboprop?

A turboprop is simply a jet engine driving a propeller. The jet engines in the King Air are mounted back to front: air enters the intake underneath the propeller and is routed under the engine before being turned up through 180 degrees to enter the engine compressor. The propeller is not mechanically connected to the engine but has a 2 stage turbine of its own that is spun by high speed air exiting the engine. The engines rotate at up to 38,000 rpm and the propeller spins at up to 2000 rpm.

Can the King Air fly on one engine?

Yes. Even at maximum weight, one engine produces enough power to keep the aircraft climbing away from the ground.

Has it got guns?

No!

How far can it go?

Like many transport aircraft, range is a balance of fuel versus load: as passengers are added, the fuel carried must be reduced to keep the aircraft below its maximum take-off weight of 5.66 tonnes (12,500 lbs). In multi-engine pilot training, it is essential that student pilots experience long-range high altitude operations and the complexities of international operating procedures. On a typical overseas training flight, the King Air could fly non-stop from its home base in Lincolnshire to northern Spain, Italy or Austria.

How high can it go?

Although the King Air B200 is cleared to fly at 35,000 ft, our own regulations restrict us to 28,000 ft. The air inside the cabin is pressurized to keep the cabin altitude below 8000 ft.

Why are the leading edges of the wings and tailplane black?

The black areas are inflatable rubber ‘boots’. Using air bled from the engines, they are inflated when required to break off ice which can build up when flying in cold damp conditions.

Where do students go when they have completed the King Air course?

Most students progress to become co-pilots on the following types: BAe 125, BAe 146, C17, Hercules, Sentinel, Sentry, Shadow, Tristar and VC10. Additionally, 45(R) Sqn trains Army pilots destined for the Defender and Islander.

Leon says…

On safety

My colleagues, our supervisors at RAF Cranwell and I, have put a good deal of effort into ensuring the display is as safe as it can be while still being entertaining. The absence of a g-meter in the King Air means that our display follows
a carefully designed set of parameters and gates that ensure the loads exerted on the airframe are well within its limits. The engines have no self-limiters, meaning that, if I simply pushed the power levers (we don’t call them throttles) fully forward for full power, I could overstress the propeller gearboxes. This is further aggravated by the torque (that’s a measure of the engine power being used to drive the propellers) increasing as the speed increases, completely independently of power lever position. This means the engines need close monitoring throughout the display, and the co-pilot is responsible for ensuring they remain within limits. He is also responsible for calling out our heights and speeds throughout the display. This enables me to maximize my attention on the ever changing attitude of the aircraft, and our position relative to the display datum (crowd centre) and the display axes, while still being fully aware how close to the limits of the flight envelope we are, and indeed how close to the ground we are.

On g-limits

Although we have no g-meter in King Air, the aeroplane still has g limits: +3.17g with the landing gear and flaps up, reducing to +2g as soon as either is selected down; the negative g limits are -1.27 and 0 respectively, although we maintain a small amount of positive g at all times. While experience helps a pilot judge how much g he is pulling, by keeping to a strict profile of power settings, pitch and bank attitudes, and recovery heights and speeds, we can be confident that we remain well within the published g-limits.

On bank angles

It is widely accepted that the g experienced is relative to the bank angle – the more bank you apply, the more g you feel. This is, in fact, not true. The direct correlation between g and bank angle is only valid under certain flight conditions, most notably when maintaining altitude. It is for this reason that while you may see an aircraft at much more than 60° bank, the g load on that aircraft could be much less than the 2g normally expected for this bank angle.

On simulators

We have three King Air simulators at RAF Cranwell that we use to supplement the aircraft for student training. We have made good use of the simulator to develop the display, not only in proving the manoeuvres under normal circumstances, but also in contingency planning for potential failures. At the press of a button, we can simulate any number of failures from a simple blown fuse to a double engine failure. By combining challenging display manoeuvres with major system failures, we can be sure that the risks associated with our display are kept to the absolute minimum.

On the weather

The weather plays a major part in any display. Each aircraft type will have a cloudbase and visibility limit below which it would be unsafe to display. For a full King Air display, we need a cloudbase 2000ft or more above the display area, and at least 5km visibility. If the weather is worse, we can perform a limited display and in the worst case, a flat display with a cloudbase as low as 1000ft. On windy days, I have to make allowance for drift, so each manoeuvre, while apparently simple, could involve several power changes and invisible (to the audience, I hope) changes to our flight path to ensure that at the end of each manoeuvre we are in the right place with the correct amount of energy. Our take-off and landing direction is also determined by the wind. It is normally better to take-off and land into wind; however, the King Air has sufficient acceleration and braking performance that provided the wind is fairly light we can take-off and land in opposite directions. A simple change of direction on the towards-crowd wingover halfway through the display determines at which end of the runway we will commence our steep approach to land.

On steep approaches

The steep approach is one of the most challenging elements of the display to get right. By design, it should always be safe: we enter from the same height, at the same airspeed, in the same configuration, with idle power every time. This means that when we reach our planned recovery height, we always have a known amount of energy. By proving the safety margins at maximum weight, we can be confident that we will always be able to transition from the steep phase to a normal landing within the height available. The difficult part is judging when to commence the descent. Once we start down the slope, there is very little I can do to affect where we touch down: the entire procedure to landing is flown without adding power. If the conditions were always the same, this would be straightforward, but they aren’t: the wind can be anything from 60mph on the nose, to over 10mph from behind. I also have to consider stopping distance. If the runway is sufficiently long, I will endeavour to stop just after passing the display datum at crowd centre. With full reverse thrust selected, even with only moderate braking, the King Air stops from 115mph in about a thousand feet. That is unless there is a tailwind, the runway is wet, or it slopes. The stopping distance is also affected by the weight of the aircraft. So in judging when to commence the descent from 1000ft, I have to consider a large number of variables.

On reverse thrust

The King Air is able to reverse the angle of each individual propeller blade such that, instead of scooping air and throwing it backwards – as for normal flight – the blades slap the air forwards causing the aircraft to stop very quickly after landing. By selecting reverse thrust when stationary, the aircraft may be taxied backwards.