Another KOS
4th Jun 2003, 17:29
In a recent conversation (with a clever person), the relative merits of the EC155 and BA139 were being discussed. I postulated that the size of the engines in the AB139 - 1800shp with growth potential to 2400shp (same basic engine used in the AB609), would provide engine failure accountable performance at all but the highest altitudes.
Yes said the clever person but the running costs of such installed power are a serious downside when compared to the EC155 which has (almost) the same payload space with much lower DOCs.
We progressed to growth potential for the AB139, ah he said but the growth potential will erode the excellent performance down to the average - economics will be the final arbiter of the end result. Yes said I but the economics of a potential accident must be somewhere in the equation - stalemate.
OK clever person, said I, why is it then that the smart little twins (B427, A109E, EC135, 902 - sorry if I have missed out your little beauty) are fast reaching the stage when OEI HOGE is possible (at MUAM sea level ISA plus something).
Ah said he appoaching the check-mate stage, these twins are built to the FAR/JAR 27 Certification code which limits the growth weight to 7,000lbs. Therefore, any increase in installed power or gear box improvements can be taken as an increase in performance.
Ah said I, a win for the law of unintended consequence - and I am a little cleverer than I was.
Yes said the clever person but the running costs of such installed power are a serious downside when compared to the EC155 which has (almost) the same payload space with much lower DOCs.
We progressed to growth potential for the AB139, ah he said but the growth potential will erode the excellent performance down to the average - economics will be the final arbiter of the end result. Yes said I but the economics of a potential accident must be somewhere in the equation - stalemate.
OK clever person, said I, why is it then that the smart little twins (B427, A109E, EC135, 902 - sorry if I have missed out your little beauty) are fast reaching the stage when OEI HOGE is possible (at MUAM sea level ISA plus something).
Ah said he appoaching the check-mate stage, these twins are built to the FAR/JAR 27 Certification code which limits the growth weight to 7,000lbs. Therefore, any increase in installed power or gear box improvements can be taken as an increase in performance.
Ah said I, a win for the law of unintended consequence - and I am a little cleverer than I was.