Originally Posted by
greenthumb
I would like to know how it was possible to mix military parts with the approved civil ship and parts??? The mil parts not having a BO105 civ partnumber and no civ ticket. Over the last 20 years it was impossible to use one single screw from the mil ships on civ registered. Germany phased out so many BOs from mil service. To get very cheap. But EC prohibited strictly the use of ex-mil ships and any parts. Very strictly!
And if it was no part in the certification process aerobatics couldn`t be approved on my sight for a civil registered helicopter according to the present rules. But with the power and money of REDBULL...
I spoke with the pilot and walked around one of two D- registered BO-105, used by Red Bull some years ago.
As I remember, he said that the helicopter (built in 1974(!) is basically serial helicopter with no significant modifications, apart from all non-essetial gear removed. Only maintenance is, of course, much more intensive with many inspections, etc. It is a simple fact, that BO-105 was the first serial helicopter with hingeless rotor, and Mr. Bolkow deliberatelly beefed up the titanium hub, as no one exactly knew, how this will work. The result was, that there is a big fudge factor in rotor design, that can withstand a lot of loads, plus the design, where excessive flapping, etc. is not such a problem.
I think that BK-117 has the same rotor hub, even it is much heavier.