Skygate 911

[johndoeX]

13. You are so lost it would be funny if not so sad.

Last edited Tue May 27, 2014, 12:12 PM - Edit history (1)

>So? The Vd discussion, which you did not comment on, is not specific to small aircraft, and nothing I've said depends in any way on anything in 23.629.

Sigh... Please show me a small aircraft which has a Vmo. Wow... just wow.

> I'm not the one confusing load with speed.

Yes you are. You said...

"The way the engineers assured the planes could fly at their Vd velocities WITHOUT falling apart is by adding a 50% margin of safety." - http://www.democraticunderground.com/?com=view_post&forum=1135&pid=7451

You are wrong. But nice try at backpedaling.

>Your expert appears to be confused

Says the guy who just a few short days ago didn't even know what Vd was and thought there was a 50% margin of safety attached to Vd.... lol. Now apparently he thinks he knows more than AOPA. Too funny...

>Are you aware that people can look this stuff up on Google?

Yes. You should try it.... and don't stop when you think you have an answer which suits your bias. Because as you have seen, you tend to be wrong... alot.


The margin of safety for speed is between Vmo and Vd on transport category aircraft. Again.. small aircraft do not have a Vmo.

>At Boeing, each "Aircraft is designed to be flutter free up to 1.15 times maximum design dive speed envelope (Vd/Md) up to Mach 1.

This is not just "At Boeing". This is an FAR Requirement and applies to both Boeing and Airbus. You'd know this had you actually used google and didn't stop when you found something to support your bias. However, 1.15 does not apply in the way you think it does.

There is a theoretical margin of 1.15 for Vd under Part 25 (1.2 under Part 23), but this is theoretical and for a constant altitude and mach... ie not maneuvering... This does not apply to aircraft which are maneuvering (such as were the aircraft on 9/11).... and precedent has proven as such. Many aircraft (including Boeing and Airbus) have suffered structural failure well below 1.15Vd.

The Flight Maneuvering Envelope is posted above under FAR Part 25. It is not fake.

Again.. The "50% margin of safety" in which you claimed applied to Vd, is for G loads, not speed. You were wrong... and you will not find one pilot.. not even your anonymous 'eggspurts' at JREF who will agree with the statement you made above. But hey, if you do find one who will agree, let us know. I bet he/she/it will never put their name on it....

Watch and learn... Boeing 777 Wing Test

&feature=kp

The wing broke at 154%, it passed limit load certification. And as you can see, it had nothing to do with speed. Unless of course you think the building in which the testing was performed, was traveling at Vd.

Now go read FAR Part 25 and notice the differences between FAR Part 23 as it pertains to Vd margins.