Short Field Tailwheel Operations

My tailwheel training course in the Super Decathlon does not conform to CASA’s Part 61 Manual of Standards for the reasons explained below. 

Short Take-off

      • CASA requires take-off power to be fully applied before releasing the brakes – this is contrary to the Manual and is a common cause of nosing over.
      • CASA requires rotation at the manufacturer’s recommended speed and climb at speed for obstacle clearance – rotate speed in the Manual is 43 kts – less than the stall speed and the climb speed in the Manual is 50 kts – very close to the stall speed. The Manual warns of risk of injury or fatality in the event of an engine failure in this situation.

Short Landing

  • CASA requires application of maximum braking after touchdown at minimum speed – this is contrary to the Manual where the instruction is “brake as required” with a warning of injury or fatality due to the risk of nosing over.
  • CASA requires the trainee to calculate the landing distance and promotes the falsehood that the short field performance can be easily achieved by an average pilot – this is not true of aircraft certified many years ago. The Manual states that the landing distance data represents “maximum airplane capability at speeds shown and requires aircraft in good operating condition and a proficient pilot”.
  • CASA requires that the trainee stops the aeroplane within the calculated distance. Landing approach speed in the Manual is 52 kts which is very close to the stall speed. The Manual warns of risk of injury or fatality with this technique and I repeat the above statement – the landing distances in the Manual will only be achieved using exactly those speeds specified with the various risks of damage to the aeroplane and injury or death to the crew must be highlighted.

It is interesting to note that when Decathlons first arrived in Australia they were provided with new take-off and landing charts – so-called P charts. There was a take-off safety speed (that is a very informative term) of 58 kts. The landing approach speed was also 58 kts – about 1.3Vs. Those charts applied to the earlier model Decathlons with a lower maximum weight and have since been withdrawn.

I see that the Manual for the new Xtreme Decathlon is differs from that of the Super Decathlon by specifying more reasonable speeds – similar to these P charts.

CAAP 155-1, Aerobatics

CASA’s CAAP 155-1, Aerobatics used to be a good place to start reading about aerobatics and does include some of the information that you must know but it has a number of deficiencies:

  • it does not adequately explain the structural limitations associated with VA, Manoeuvring Speed
  • it does not have the new, additional underpinning knowledge requirements of the Part 61 MOS
  • it has not been updated with the new licensing regulations of September 2014

What is Aerobatics?

A good place to start is with the definition of aerobatics :

The International Civil Aviation Organization defines aerobatics as “maneuvers intentionally performed by an aircraft involving an abrupt change in its attitude, an abnormal attitude, or abnormal variation in speed.”

CASA used to have that exact same definition but in September 2015 they changed it to:

“aerobatic manoeuvres, for an aircraft, means manoeuvres of the aircraft that involve:

(a)  bank angles that are greater than 60°; or

(b)  pitch angles that are greater than 45°, or are otherwise abnormal to the aircraft type; or

(c)  abrupt changes of speed, direction, angle of bank or angle of pitch.”

Why did CASA change their definition of aerobatics?

The USA and Europe have definitions which are almost exactly like the ICAO definition. The USA has an additional rule requiring the wearing of parachutes in some circumstances when an aircraft exceeds 30 degrees of pitch or 60 degrees of bank relative to the horizon; their definition of aerobatic flight, however does not specify pitch attitude or bank angle. EASA has an additional rule clarifying that training undertaken for a licence is not aerobatics.

Why did CASA remove the word “intentionally” from the definition of aerobatics? Consider what CASA requires for training towards a licence and consider whether any unintentional wing-drop etc is aerobatics per CASA’s definition. Not a problem of course if it is a dual flight and the instructor has an aerobatic training endorsement.

Have fun!