Thanks bpaggi, I was also involved in the AW 139 thread.
Are these [high DA] rigs penalized and therefore do not deserve a Cat A operations in order to allow a decent payload or range?
That is the crux of the discussion; who gets penalised? Should the high DA rigs be penalised for the low DA ones, or the low DA for the high?
The advantage of using the low DA rig as the benchmark is that all operations can be run economically, but advantaging the high DA requires too much excess power for the low DA and thus creates a loser.
Look at it this way: 10 pax CAT A power to a high DA rig can be achieved by a 10 pax capacity full CAT A machine, or by a 15 pax capacity limited CAT A machine carrying only 10 pax. When that same machine is now used on low DA rigs, the 15 pax machine now carries 15, but the 10 pax can still only carry 10 pax! And to achieve the 10 pax high DA CAT A, both machines would need comparable engine and drivetrain weights and fuel consumptions wouldn't they? When they move to the low DA rig, the 10 pax machine is carrying that higher consumption and drivetrain weight without getting any return, but the 15 pax machine gets to carry 5 more pigs.
So if you work in an area with large DA variations, it pays much larger dividends to use the 15 pax limited CAT A machine doesn't it? And everyone else who gets the 15 pax machine and can accept the 0.17% exposure can save money on the high DA days too.
That saving should be then invested in anti CFIT measures rather than full CAT A over all rig types - especially given CFIT is the more prevalent of the dangers.
I do think the AW139 is a terrific helicopter
Spot on. It is fantastic and I certainly dont wish for anything else for my christmas present this year!!!! But pretty soon, they will be expanding the weight upwards and out of the full CAT A capability and it will also become an economical one across risk profiles. Same way the A109E is now not a "Full CAT A" machine post 3000kg upgrade - but you can still operate it full CAT A if you want to restrict it to 2850kg. At least Eagle 86 told me so!
