7.4 AFM – High ambient temperature operations
Background: The Convenor received the following information of interest. The attached CASA response confirms this is not a CASA/RAPAC responsibility – rather manufacturers – but RAPAC members should take note:
“Many areas of Australia have encountered above 40 degree C temperatures in recent times, and will likely encounter them again in subsequent years. The attached map from the BoM website chronicles the period 1 November to 31 January.
CASA was asked: if an aircraft's AFM caps performance data at 40C, can the aircraft still legally fly when the ambient is above 40C? Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded". This is a significant announcement and has widespread implications. Insurance companies rely on a pilot's compliance with CASA's rules and regulations when considering if a claim is to be processed.”
Discussion: The Convenor indicated that the item had been included for the information of members and to raise awareness of the issue.
Mr Walker confirmed CASA’s position that aircraft needed to be operated within the parameters published in an aircraft flight manual and there was no provision to extrapolate performance data beyond that provided.
if an aircraft's AFM caps performance data at 40C, can the aircraft still legally fly when the ambient is above 40C?
Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded".
Where do CASA's declared density altitude charts fit into all this, they don't mention temperature
reading thru 6 pages of responses, where is this going?
What if you cannot determine your weight !?!?! (okay I added the !?!?!)
then you use the MTOW for the ac...FFS. (sorry, but if you cannot determine your weight, how did you determine loading for the ac? )
In reality, if you are a driver and cannot figure out your MTOW, then it does not matter what the temperature is, you should be restricted from taking off.
if an aircraft's AFM caps performance data at 40C
including the range for which performance data is provided,
What is MTOW for the ac based on?
The MTOW and associated parameters with ISA with airport altitude and temperature are well defined.
ISA and ISA d....is there an understanding of the ISA temp/altitude, (and MTOW) and what one must do when NOT within those parameters???
With the ISA D, you can determine what MTOW is based on per the temperature D. If the temp is higher than listed, you need to weight limit, and calc the new MTOW.
When ac look at restricting ops with temp, it means that IT cannot meet DEP obstacle clearance EO, and UNLESS you have an EO approved procedure, thus must follow the SID procedure.
In reality, I have significant concerns with drivers who have no understanding of MTOW, associated temperature limitations with the associated effects, nor the comprehension of the necessity to calculate take off weights for their aircraft..