ATPL - performance and loading question
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ATPL - performance and loading question
When calculating a SAR or SGR.
How do you convert mach to TAS using the whizz wheel or BASIC rule of thumb arithmetic?
ie
"what is the SAR for a 727 that weighs 72,000Kg cruising at FL350 @ Mach .82 and ISA temp?"
SAR = TAS/FF*1000
TAS = ??
FF = 4410KG/h(normal cruise at mach .82)
How do you convert mach to TAS using the whizz wheel or BASIC rule of thumb arithmetic?
ie
"what is the SAR for a 727 that weighs 72,000Kg cruising at FL350 @ Mach .82 and ISA temp?"
SAR = TAS/FF*1000
TAS = ??
FF = 4410KG/h(normal cruise at mach .82)
If you have a CR-2/3
Find the ISA temperature at FL350 = -55
Go to the Mach Index window on your CR-3 and line up -55.
On the Gray outer scale of your CR-2/3 (which you would normally use for minutes in a fuel flow calculation) line up 82 (which is Mach 0.82) The outer scale will show a TAS of 470kts
SAR = 470/4410*1000
SARs are pretty useless, SGRs are used everyday and something you will be using a lot in Flight Planning.
Good Luck.
Find the ISA temperature at FL350 = -55
Go to the Mach Index window on your CR-3 and line up -55.
On the Gray outer scale of your CR-2/3 (which you would normally use for minutes in a fuel flow calculation) line up 82 (which is Mach 0.82) The outer scale will show a TAS of 470kts
SAR = 470/4410*1000
SARs are pretty useless, SGRs are used everyday and something you will be using a lot in Flight Planning.
Good Luck.
