T28 wrote:
242 / 170 = 42.4%, no structural damage.
I recall a case where a Mooney 201 suffered massive damage (write off if I am not mistaken) after entering a thunderstorm cloud near Salzburg many moons ago. It experienced massive turbulence and up and down drafts exceeding the g-loads and during the event also exceeding Vne several times.
After they left the cloud, the airplane flew on to it’s homebase, with the pilot not noticing anyting wrong in flying. It was however found that the wing was bent upwards and other massive damage had occurred. But it did not let go.
About 2 months before he retired, I had a contact with Mike Miles, the legendary test pilot of Mooney. He mentioned that so far there has been only one break up of a Mooney in a thunderstorm cloud about 30-40 years ago. That is the only Mooney M20 ever to break up in flight. I think that is no mean achievement.
Needless to say I feel VERY safe in that regard with the Mooneys.
but “x% of maximum speed where it has been demonstrated that they won’t fall off…”
Isn’t one required to show that there isn’t flutter taking place?
I know someone who built special hardware for detecting that (proprietary, so I won’t post details).
Ibra wrote:
How far you can go beyond VNE before wings are pulled? it lost it’s wings somewhere 40%-50% more than VNE?
Definition of Vne is not “x% of minimum speed where wings are sure to separate” but “x% of maximum speed where it has been demonstrated that they won’t fall off…”
You are right I forgot VNE of vintage short body M20E is near 170kias (used to mid & long body ones going near 190kias)
How far you can go beyond VNE before wings are pulled? it lost it’s wings somewhere 40%-50% more than VNE
220 / 163 = 34.9%, wing separation.
242 / 170 = 42.4%, no structural damage.
T28 wrote:
Not sure how 245 kts without wings is exactly a “winner” in this context?
How far you can go beyond VNE before wings are pulled? it lost it’s wings somewhere 40%-50% more than VNE?
Thanks for that reference, but I think we already have a winner 245kts on fiberglass !
this conditions, 220 kts (405 km/h) and over 10 G, load the aircraft wings structures separated from the airframe
Not sure how 245 kts without wings is exactly a “winner” in this context?
T28 wrote:
In a recent loss of spatial orientation in IMC event in Canada a M20 F has been clocked up to 242 kts IAS (70kts above Vne) with no wing structural damage.
Thanks for that reference, but I think we already have a winner 245kts on fiberglass !
https://www.euroga.org/forums/flying/12331-pipistrel-virus-i-b939-doing-245kt?page=1
VNE certfification for CS23 aircraft will only show you have no flutter beyond VD (VD approx 50*SQRT(Wing Load in lbs/ft2) ) in turbulent conditions and set VNE = 0.8*VD, some can push VNE higher by diving beyond VD untill flutter happen or the wings breaks
I fly Pilatus B4-PC11, it has 5lbs/ft2 with VD at 120kias and VNE at 130kias, I am happy to dive it up +120kias then loop/barrel in calm evening aerobatics but when doing aerobatics midday in turbulent thermals, I tend to chiken out at 110kts due to asynchronous hand & teeth mouvements even when wearing parchute (it’s metal structure does start singing like organ piano and I was never comfortable, most of my glider flying was on fiberglass with air whistling only)
the Mooney wing was tested to 9G (pilot neck break first) but it can’t fly more than 200KIAS due to low wing load & flutter
In a recent loss of spatial orientation in IMC event in Canada a M20 F has been clocked up to 242 kts IAS (70kts above Vne) with no wing structural damage.
Fenland Flyer, aircraft are built by engineers so that they are safe to fly by pilots. Being ignorant of engineering detail is quite probably something that allows you to enjoy your flying more than those who fret about engineering detail.
Personally I’m somewhere in the middle as I am an engineer but not in aircraft so I like to read these technical posts in the hope that I might accumulate more useless (to me) facts. It’s the curse of an enquiring mind.
