Out of Ground Effect

I don’t remember exactly when I fell in love with the prospect of flying.  I didn’t know any pilots growing up.  My first stepfather worked for the now long defunct airline Braniff, and because of that, there was some trips in a jet airliner.  But that isn’t flying.  You’re packed into a cigar tube, fighting for elbowroom, children are screaming, the air is foul with perspiration and cigarette smoke.  Yes, cigarette smoke, it was the late 60’s and early 70’s after all.  If you’re lucky, the takeoff or landing was a bit bumpy, giving you some sensation of flight, but otherwise…blah!!

I do know when I fell in love with helicopters though.  Way back, in the dark ages before video games and the internet, we did things like play board games, go outside, occasionally watch one of 4 or 5 TV channels, and for us boys, we built models.  As my model building skills improved, so did the complexity of the models offered.  One of those advanced models was an AH-1 Cobra gunship…Air Assault!

It didn’t take much persuasion from my cousin, who was an Army vet, to join the Army so I could fly one of those bad boys.  I was still pretty young when that decision was made.  Therefore, like any young man, I probably changed my mind several times.  Nevertheless, by the time I was in high school, all I wanted to do was fly a helicopter.

Oh, and be a writer…but we covered that.

As I entered into flight school, I did so with no apprehension.  I was nearly fearless as a kid and was sure that flying would be my thing.  As I stated in First Flight, and First Flight Part Duo, there was a couple of moments of apprehension.  However, for the most part, I feared little when it came to the prospect of flying bad-ass helicopters.

This near fearlessness continued right into flight school.  There were a couple of scary moments.  A near midair collision in primary flight training, the hovering autorotation incident in A Moment in Chaos, and a second near midair in tactics training much later in the program.  Some of those scarier moments, I will probably put down in words and share them with you at a later date.

However, being fearless doesn’t mean I was a fool.  We practiced a maneuver in both primary flight training and tactics that I did not like at all.  Well, let me take part of that statement back.  As I write this, I seem to remember it not bothering me much in primary flight training.  At least not until I saw my flight instructor visibly relax when we transitioned out of the maneuver back to regular flight.

The Amy called the maneuver, Out of Ground Effect Hover.

Ground effect is the effect of the helicopters proximity to the ground on its flight characteristics.  The thing that makes a helicopter launch into the air when it is accelerating forward is the fact that if out flies its own rotor wash, or ground effect.  Helicopters are terribly inefficient in all phases of flight, but when its close the ground, it creates so much turbulence in the air, that it is working hard to maintain a three foot hover.

Done with my boring rotor wing aerodynamics class.

However, when it is that close to the ground, there is plenty of inertia in the rotor system to touch the aircraft down gently if the motor stops.  I will avoid the physics lesson that goes along with this principle.

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