ARTICLES

 

         

Killer Clouds

 

This past summer there were several accidents in which there were multiple fatalities resulting from the helicopter pilot’s decision to fly into night time conditions that resulted in the loss of control of the helicopter. In one case the private pilot was non instrument rated, in the second, the pilot was a Certified Flight Instructor, and in the third case the pilot was a Certified Flight Instructor certified for Instrument training in helicopters. Each of these pilots made the decision to fly their helicopters into IMC (Instrument Meteorological Conditions) at night and the results were the deaths of every person on board.

Is it unsafe to fly at night? Night flight in helicopters is safe as long as the pilot receives proper training in night helicopter operations and the pilot has the discipline to make intelligent and informed go-no go decisions.

We fly our R22 at night for pleasure and flight training but have several conditions that must be met prior to taking such a flight. The first condition is that the weather report from Flight Service shows NO POSSIBILITY of clouds along the proposed flight path. You notice the statement “no possibility”, not probability. If there is any possibility that clouds could be encountered along our flight route, we do not fly at night. The second condition that is required is that we have adequate ground lights in the area we are planning to flying over. And the third requirement is that we have adequate fuel, flashlights, etc. to make the flight safely.

At Homer Bell’s fly in this past summer I was chatting with a group of pilots and at least 2 other helicopter flight instructors about the three fatal accidents involving the R44’s that were flew at night into IMC. I posed the question “what would you do if you are flying at night and suddenly you loose all outside reference due to flying into a cloud?” Every one of them agreed that the proper response would be to immediately execute a 180 degree turn and exit the cloud in the direction from which you entered it.

This might be the proper response in a fixed wing airplane but not in a non-instrument certified helicopter. Although most helicopter flight instructors teach that a 180 degree turn is the safe way to get out of a cloud, that decision will most likely be a fatal mistake if the pilot is not current on flying by his instruments. The only way to safely execute a 180 degree turn in a helicopter without outside reference is by the use of the gyroscopic instruments installed in some helicopters. Without a directional gyro and an artificial horizon it would be near impossible to maintain flight for more than a short time.

Airplanes are inherently stable. If you take your hands off the controls of most airplanes, they will continue to fly due to their built in aerodynamic stability.Helicopters are inherently unstable. The only stability in a helicopter is the pilot at the controls. The pilot keeps the helicopter stable by visual reference to cues coming from outside of the cockpit. If the helicopter pilot were to let go of the controls, in only a very few seconds the helicopter would go totally out of control and self destruct. Bearing this in mind, if the helicopter pilot losses his outside visual reference cues, he is unable to keep the helicopter stable. The better a helicopter pilot is trained in instrument flight in light helicopters like the Rotorway, Safari, Hughes, Robinson, etc, the longer he may be able to keep the helicopter right side up, to a limit, providing the helicopter is equipped with the appropriate gyros. If a pilot of a non-gyro equipped helicopter were to enter a 180 degree turn without outside reference, the helicopter could very quickly go out of control.

Of the 3 fatal accidents that we mentioned above, (all were in heavier R44 4 place helicopters which are more stable than the light helicopters that most of us fly) one pilot was an instrument instructor and another was instrument rated. All on board all three helicopters died.

Recently a student of mine and I made a ferry flight from San Antonio, TX to Missouri in a Hughes 269B that he had just purchased. We decided that this long trip would be a great opportunity for some cross country flight training. The flight was progressing uneventfully and we stopped in Clarksville, Arkansas to refuel for the night portion of the trip. After topping off our tanks and checking our flashlights, we called flight service to check on the weather along our proposed 2 hour leg. Flight service reported that there were no clouds along the route and it looked like it would be a perfect night flight to bring us on our final leg home. My student was enjoying the view of the stars and scattered lights from various towns and ranches on the ground as he piloted the helicopter along our route.

About 20 minutes into our night flight we lost all outside visibility without warning. The millions of stars and numerous ground lights just suddenly disappeared from view. Instantly I recalled the three recent fatal accidents involving experienced pilots in their R44 helicopters that flew into IMC at night with fatal results.

I have always taught my students “if in doubt, auto out” . Although we never expected to fly into a cloud at night much thought had been invested on that subject. The decision was made that the best way to stay alive, should one totally loose outside visual reference, would be to immediately enter an auto-rotation descent. While the helicopter is in an autorotation, it is in the most stable flight configuration that it can attain. The up-flow of air through the rotors keeps the rotor system facing up and the helicopter hanging below it until the pilot is able to see the ground and flair. At least it was a plan of action to take should one ever loose outside visibility although up to this point I had never been in a situation to put my theory to the test.

On this particular flight we encountered that very situation. There were no clouds at all predicted along our route of flight. The sky was perfectly clear allowing visibility for miles in the perfectly clear air. When visibility was suddenly lost I immediately lowered the to place the helicopter into an auto-rotational descent.

It seemed like we were in that auto for a full minute but it was probably more like 20 seconds. This particular helicopter was not equipped with an artificial horizon, directional gyro, or even a vertical speed indicator. By focusing on the rotor rpm and the airspeed indicator I was able to keep both within their limits. We both kept a watch outside hoping to see a glimpse of the ground or trees so that a flare could be made prior to impact.

As we continued to head earthward in a very stable and upright auto-rotation, the smell of wood smoke filled our nostrils. We had flown into a cloud of smoke that flight service did not know would be there. All at once the lower portion of the wind screen filled with numerous ground lights and even more bright orange bands that turned out to be flames from a controlled burn being conducted by the Arkansas Division of Forestry. With outside visual reference restored I added power and collective pitch and we resumed normal powered flight.

We realized that we had unwittingly entered a very dangerous situation, one that could have produced fatal results, and yet we had survived. The reason that we did survive was that I had a plan of escape already thought out and decided upon should we enter a cloud at night. When the unexpected finally happened I was able to react immediately .

Once we were clear of the smoke cloud we executed a 180 degree turn, and headed for the nearest airport. We set down, parked the helicopter, borrowed a courtesy car and went into town for a meal and a motel. I was convinced that we both had experienced enough night flight for that particular evening.

The next day we got up early, had a great breakfast at the local diner, and then returned the courtesy car and headed home. When we got to the area where we had encountered that killer smoke cloud, I looked down at the rough terrain below us and thanked God that we were not the subject of a Civil Air Patrol search for missing red and white helicopter. I am now convinced more than ever before that if I ever again loose outside visual reference (I don’t plan on it ever happening again!) I will once again immediately enter an autorotation and live to tell about it.

Refer back to the question that I posed to the CFI’s and pilots at Homer’s last year: “what would you do if you are flying at night and suddenly you loose all outside reference due to flying into a cloud?” Their unanimous answer was to immediately execute a 180 degree turn to fly out the way they came in. What would you do?

Orv Neisingh is an FAA certified Helicopter Flight Instructor with Sho-Me Helicopters, LLC. He offers helicopter flight training in your own helicopter either at your location or at his facility in the beautiful Ozarks of Missouri. He also can assist you in the rigging and balance your rotor system as well as instruct you in maintenance procedures for your helicopter while you are receiving your flight training. Sho-Me Helicopters welcomes you to come to their helicopter flight training facility in Missouri where they provide full RV hook-ups and also offer free room and board to their students in the family home. Orv schedules one on one instruction meaning when you hire Orv, you are the only student that he works with during that time period.

 

Orv Neisingh

Sho-Me Helicopters, LLC