Hasell Checks and Why Do we Do Them

Aimed at – entry level aerobatics

HASELL checks are designed to make sure everything is good prior to doing stuff that might result in the aircraft entering an unusual attitude, being on the fringes of control or being out of control and consuming a large amount of height during the recovery process. Of course the term “doing stuff” is broad and ranges from stalling to spinning or aerobatics. A typical use of HASELL checks would be prior to practicing stalling during the PPL course. Of course if a series of stalls is being practiced then most of the HASELL check remain unchanged so abbreviated checks are completed.  These are HELL checks

Height –  sufficient to be sure of recovery by the base height which is normally 1,000 ft

Airframe – correctly configured for the maneouvre, e.g. flaps up, windows closed, correct fuel tank selected perhaps booster pump on

Security – straps tight and locked, no loose articles

Engine – T’s and P’s good, mixture appropriately set for lowest anticipated height

Location – Not in or near controlled airspace, not above built up areas, a suitable location

Lookout – a proper lookout to ensure no collision risk will occur.  This normally involves a minimum of a 180 degree turn or 2x 90 degree turns.

When we start aerobatics we religiously go through HASELL checks and the abbreviated HELL checks.  As training progresses we end up doing these almost constantly throughout the flight although for the sake of brevity we don’t call them out so the outside observer may not even realise they are being done . To emphasise the point at any phase during aerobatics the pilot must be fully aware of his height is and what his base height is and the maximum height of the ground and obstacles beneath him. Similarly a constant 360 degree lookout is essential.

In future articles I will consider this presumed knowledge.

CTA – spinning and upset recovery course