Burning jet fuel while going nowhere over Richmond, VA
Today was my first day flying “Sky 12”, Richmond, Virginia’s only traffic helicopter. Sky 12 is a Bell 206 Jet Ranger that has been fitted with a Wescam gyro-stabilized camera mount and a microwave link back to the TV station. Normally the helicopter is operated by a single pilot who simultaneously talks to the TV news producer, aims the camera, and positions the aircraft. However, for $125 per hour the contractor, HeloAir, sells the right seat to rated helicopter pilots who want to build 206 time or, like me, just have some fun. The left seat is occupied by an expert with thousands of flying hours, a flight instructor’s rating, and years of experience doing TV work. This morning it was Alisa, one of only a few hundred female commercial helicopter pilots in the U.S. [Young female readers: this is a great career for a woman because there is a certain amount of preferential hiring on the basis of sex and employers want pilots who are as light as possible so that they can fill the rest of the ship with equipment or passengers (just don’t expect to earn more than $60,000/year and much much less for the first five years)].
Starting a turbine engine is more complex and fraught with potential for expensive damage than starting a piston engine. You begin by holding down the starter button and holding it until the turbine has been spun up to about 15%. Then you roll the throttle to flight idle, which introduces fuel into the turbine. You continue holding the starter button down until the turbine has reached 60%, at which point turning, burning and cooling become self-sustaining. If at any time the turbine outlet temperature goes into the red, indicating a “hot start”, you must roll the throttle back to “off” to take the fuel out of the system while again keeping the turbine rotating with the starter so that it gets cooling air.
Once started we lifted off from the ramp and climbed to 1200′ to circle downtown Richmond and await instructions from the station. Upon being told to film a particular bridge we would try to approach it so that we were heading into the wind. Then we brought the helicopter to an “out of ground effect” (mid-air) hover, with the airspeed coming down below 30 knots. Remember that we were into the wind so even if we weren’t moving over the ground we were still flying forward through the air to some extent. This maneuver violates every principle that I had been taught in the light piston Robinson R22 during training. The R22 has almost no inertia in the rotor system. If the engine quits the blades will spin down dangerously slow within about 1 second. You must immediately lower the collective to begin gliding but also usually pull back on the cyclic to transfer some of the forward speed energy into higher blade RPM. If you didn’t have any forward airspeed to perform that flare the blades potentially could spin down below about 83% in which case you fall like a rock and can’t recover without restarting the engine. The Bell 206, by contrast, has a lot more inertia in the engine, spinning at 30,000 RPM, and the heavy rotor blades. In the unlikely event that the engine were to quit there would be plenty of time to notice, react, lower the collective, and push the cyclic forward to regain airspeed to be used at the end of an autorotation the ground.
The Jet Ranger is mostly easier to fly than the R22 because it is so much heavier and therefore more stable. Transitioning pilots will need to get used to a bit of lag after power adjustments are requested, watching the ball instead of yaw strings and using more anti-torque pedal in general, and the lack of feedback from the cyclic due to the hydraulic boosting.
One thing that I loved about the Jet Ranger was the lack of vibration in the ship overall and in the cyclic. Some R22s feel like they are about to come apart and, even if you aren’t worried, the vibration is fatiguing. Whether that smoothness is worth an extra $500 per hour is another question…
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