Buckle Up; It’s Bumpy Out There
By Steve Sparks
Turbulence is one of Mother Nature’s most feared invisible forces. It can cause helicopters to behave like contortionists, shaking violently while trying to escape its clutches. Unfortunately, current technology does not allow us to accurately predict its location or intensity.
It seems that crosswinds and turbulence are delighted to hang out near helicopter landing sites, just waiting to ensnare their next victim. Operators are encouraged to obtain additional practice with their most trusted flight instructor to be prepared for any unexpected turbulence that may occur. Pilot proficiency is the surest way to send this despicable villain howling away in the wind.
When discussing turbulence, there is a strange phenomenon roaming the halls of aviation. This can influence pilot performance, regardless of experience. No, this phenomenon is not mentioned in any FAA handbook, so don’t waste your time looking. Here’s a hint — it’s man-made.
The phenomenon is pilot-induced turbulence (PIT). Unfortunately, some pilots create more turbulence from their own sloppy flying than what is caused by Mother Nature. PIT is often worse than plain old turbulence itself. Sound strange?
For pilots striving for smoothness, professionalism, and passenger comfort, PIT is easy to notice and even easier to feel. Yes, this habit can be hard to break, but it is also easy to solve. A little self-awareness goes a long way in smoothing things out.
With this in mind, pilots are cautioned to pay closer attention to their own jittery habits while on the flight controls, because passengers ultimately feel the effect. PIT can be reduced and even avoided with proper training and practice.
Mechanical turbulence is another factor we need to consider, especially during landings. Mechanical turbulence is generated by seemingly harmless winds blowing around man-made or natural contours, causing airflow to churn from its natural state. These conditions often lead to unpredictable circumstances for unsuspecting pilots. Mechanical turbulence can interfere with a pilot’s stabilized approach without warning, throwing them off-kilter.
The unintended consequences from hangars and other poorly planned structures near landing sites can be devastating, but pilots can reduce their risk by maintaining a little extra airspeed while on approach to a landing zone. Awareness is key here: by expecting increased turbulence when landing in tight areas surrounded by buildings or structures, you will be better able to compensate for it.
Clear as Mud
Clear-air turbulence is one of the strongest forces in Mother Nature’s recipe book. It is often generated from rapid atmospheric changes, narrow pressure gradients, erratic jet streams, and thunderstorm development. Clear-air turbulence packs a mean punch, leaving pilots feeling dazed and confused.
For unexpected encounters with clear-air turbulence, pilots should try to maintain aircraft attitude. From a priority perspective, maintain attitude control, slow the aircraft to or below minimum controllable airspeed, and confess your situation to air traffic control. In most cases, pilots are wise to make an unplanned stop to wait these conditions out, rather than pressing on.
Since turbulence can lurk at any altitude, pilots and passengers should keep their seatbelt shoulder harnesses fastened at all times. This is the surest way to prevent injury and to defend against unintentionally bumping flight controls or switches in the cockpit. There have been cases where turbulence has knocked pilots unconscious from hitting their heads on cockpit structures. Talk about being knocked for a loop.
Landing in gusty crosswind conditions requires skill in a multidimensional phase of flight. Pilots have to quickly handle a variety of forces being exerted on the aircraft. Keeping one’s cool while maintaining positive control is the name of the game.
Plan for the Unplanned
Prior to landing, pilots should always rehearse what their Plan B is going to be, should excessive turbulence factor in. Contingency planning eliminates a lot of pressure on pilots and can increase safety exponentially. Executing a timely go-around in response to a botched landing is smart. Cutting your losses early and getting away from the surface is the surest way to avoid disaster.
Regardless of technique, landing in gusty turbulent conditions requires helicopter pilots to continue flying their aircraft even after touchdown. Just because a pilot feels the landing skids touch the surface does not mean it’s time to take a breather. Any momentary letdown could result in loss of control, so remember, never ever stop flying the aircraft until it is safely secured on the pad.