Hot, High, and Heavy in a Helicopter

My main activity this week was taking delivery of a new Robinson R44 helicopter, which a friend and I are going to use for some video and still photography on the West Coast before bringing the machine back to East Coast Aero Club at Hanscom Field (Bedford, MA) to serve as a $299/hour trainer for folks who don’t want to deal with the weight constraints and ultraresponsive handling of the R22.

Mechanically and cosmetically the helicopter has been more or less flawless so far. One fuel drain has been leaking and the engine is very slow and reluctant to cool down in the hot (30-40C) ambient temperatures here in Southern California.

I wanted to see how the machine would perform at high altitudes, which is where a lot of helicopter pilots get into trouble. In the thin air, you need more power to keep the (rotary) wing flying. The non-turbocharged engine, however, begins to lose power output as soon as you climb above sea level. The slower you go in a helicopter, e.g., when approaching to land, the more power you need. This combination leads to a lot of accidents when folks slow down trying to land at a high altitude airport.

Our experiment involved filling the helicopter up with maximum fuel and loading three guys, including myself, into the cabin. We proceeded to depart the Los Angeles Basin for Big Bear, which is at 6700′ above sea level but sported a density altitude of 8600′ (helpful digital sign in the runup area), thanks to the hot temperatures. The other two guys were Lib and Gareth, local flight instructors from Universal Air Academy in El Monte, California, who have a lot of experience going up to Big Bear. I was on the controls.

We flew a shallow approach to the runway at Big Bear, with the intention of flying a low approach only and never getting below the 20-knot (approx) airspeed that is the boundary of “effective translational lift” (ETL), a speed at which the rotor system is getting clean air and operates much more efficiently than in a hover. The discipline of saying “we are not going to slow this helicopter down or do a real landing” is important. Most problems in aviation stem from overcommitment to a challenging plan, e.g., landing in a crosswind or on a short runway.

We had lots of reserve power available, according to the gauges, and we climbed out nicely from our low approach. For the next approach, we decided to attempt landing. If you don’t have enough power, you can always slide the helicopter onto the runway at 20 knots. With good technique and smooth control inputs, however, it should be possible to arrest the descent into a hover. I did manage to get the ship down to a 2′ hover over the runway, with 1″ (out of 21 and change) of manifold pressure to spare. We taxied into the ramp and had breakfast at the locally renowned airport restaurant.

Our next stop was the big airport at Palm Springs. The Atlantic FBO there has an outdoor swimming pool and Jacuzzi for visiting pilots. We had a salad at the adjacent restaurant, then began to feel physically ill from the 100-degree heat. We borrowed a car from Atlantic, a white Chevy Cobalt, and decided to kill some time at the nearby airplane museum, packed with airworthy WWII military planes. As I turned left onto the four-lane moderately high-speed local road, an SUV came up on our tail and tailgated us for awhile, honking repeatedly. I stayed in the left lane, however, because we didn’t know exactly where the airplane museum was. After about three quarters of a mile, we pulled off into the left turn lane and the SUV driver pulled alongside, continued honking and gave us the finger. He appeared to be over 80 years of age. Lib and Gareth were almost doubled over with paroxysms of laughter.

We went back to El Monte. Bryan Robinson, a 10,000-hour pilot originally from Scotland (no relation to Frank Robinson, the engineer behind the R22 and R44), took me out to practice settling with power and autorotations. Bryan is truly the master of all things rotary-wing and has flown almost every kind of fancy jet-powered helicopter. His favorite helicopter? The little R22, because it is the most responsive. Bryan lent me his new Toyota Prius so that I could do some shopping. If you don’t need to keep bicycles inside the vehicle, which is what attracts me to minivans, the Prius seems like an almost ideal car.