A bit more professionally edited summary of AirVenture 2016
A friend sent me this collection of photos from Oshkosh 2016 this morning. I think they capture the breadth of the event over all kinds of aviation pretty nicely.
I was intrigued by the Staggerwing with the the VT (Indian) registration, until I noticed the little N-number under the tail. Must be something in the plane’s past. The photo of three Howard DGAs in a row also got my attention, as this would probably be the ultimate going places plane for me, if I wanted to pay the fuel bill for 450 HP. I wouldn’t mind the Swearingen SX300 either, and it’s a lot more efficient.
Who mounted the DA-42 on a steel post??
The EAA is homebuilt, warbirds, vintage, aerobatics, LSA, ultralight and from 2015 also the “IMC Club” created to promote instrument flying, training, proficiency and safety. The only thing lacking is “contemporary” certified GA although that was not exactly lacking on the “sales” stands. What exactly is vintage anyway? 30 years, 50, 70 ?? IMO vintage is a restaurd and usable older aircraft that is not (factory) produced anymore, but I don’t really know what the “correct” definition is.
LeSving wrote:
I believe this to be the one where the seat fell out? (and the pilot with it). This was a prototype as far as I can remember, done under high G testing.
No, it was neither. It came apart during a level off in around 1000 ft out of a shallow dive from 1700 ft at around 200 to 240 km/h IAS. The owner had requested to use emergency parachutes instead of the BRS, but that was denied by the “authorities”. So the BRS could only save one of the persons on board. The BFU found out, that the wings had undergone static load tests, but the load carrying structure within the fuselage had not been tested. They FEMed the structure as a box beam, but installed a C-shaped beam as primary load-carrying structure. There were no calculations in the built configuration. There were no calculations with a correlation of stick forces. That teh BRS worked was just a coincident, there wasn’t much left and the BRS would have only worked for the engine. The ASI markings did not fit the requirements of the certification standards, the yellow arc began at 250 km/h instead of the correct 160 km/h. The low figure was a result of the minimum requirements for the load carrying ability of the structure. Furthermore, the requirements which the “certification” of the Dynamic was based on is much lower than the corresponding CS23/FAR23 and CS22. Especially the conditioning of FRP-structures differ or is not prescribed in the microlight requirements. It wasn’t absolutely certain that this accident was based on the slack certification work, mainly because there were only hints to the actual loads at the time of structural failure, but it was without doubt contributing.
And this is why you need proper independent certification that finds severe mistakes. Even the most capable engineers do make mistakes and some of them can be lethal in an airplane – they have in the past and they will continue to do so. In the wake of this and two similar accidents, the requirements for microlights in Germany have been altered.
Here is the report (in German)
mh wrote:
And this is why you need proper independent certification that finds severe mistakes
Yes, but only on certified aircraft. Besides, for å light aircraft an industri standard should be møre than enough along with testing.
And this is why you need proper independent certification that finds severe mistakes
Yes, but only on certified aircraft
You are kidding, surely? Most people who buy a UL, a kit or a homebuilt built by someone else have no more clue about the design margins than those who buy a certified type. Nobody expects to buy a death trap.
Peter wrote:
Most people who buy a UL, a kit or a homebuilt built by someone else have no more clue about the design margins than those who buy a certified type. Nobody expects to buy a death trap.
non-certified means non-certified, there is no way to escape that. Lots of people fool themselves by thinking that “my” aircraft is so fast/advanced/cool and so on, the designer certainly is a genius etc etc and therefore it must be as safe, or safer, than the traditional off the shelves spam can. Certification means exactly what mh say (among other things). The design, the materials, the build methods, the subcontractors, the factory – just about everything – has been gone through by several independent engineers and checked against standards and best practice. There are, in theory at least, no un-turned stones in a certified aircraft. Therefore, in theory, a certified aircraft must be safer than a non-certified aircraft.
In practice though, this is not what the statistics show. Un-certified aircraft have no more accidents due to structural failures than certified aircraft. You can single out examples from both “worlds”, examples that are so few they are statistically insignificant. Why is that? The reason is of course that certification of light GA airplanes is like shooting sparrows with a cannon, when a simple pea shooter would do just fine. Certification is not the only way to weed out design mistakes. That pea shooter can be builders that build experimental aircraft from kit or plans. They discuss every single detail. As the saying goes; you can build a plane in 2 years, but if you are an engineer, multiply it by 3 An experimental aircraft is essentially 100% open for anybody to scrutinize all they want, and anybody does, and do small improvements here and there, needed or not. The potential fatal design errors are simple extremely unlikely to happen, because they surface ASAP, often in very unpleasant “debates” on the internet. The wing spar on the RVs and the Cx-4 and -5. Anodized wing spars (or RVs). The crank shaft of the Aerovee engine, The usage of SS fasteners on the Sonex airplanes. Usage of 6061 instead of 2025 on several aircraft, and billions of smaller details.
With factory built microlight things are different. The design is not “open”, and trust has to be put on the manufacturer, blind faith if you want. But engineers are engineers. They have an urge to make thing as good as possible and discuss things openly among themselves, also across companies (which often terrorize the more “commercially” adapted persons opting for secrecy). Anyway, with MTOW of 450 kg, BRS (enforced by the government or voluntarily), some minimal scrutiny of the design by some “authority”, there really are not much left that can kill.
Another aspect is that a person has a life. He is entitled to manage the risk any way he chooses. That is a major aspect of living a life. Making an aircraft for commercial transport is something entirely different than making an aircraft for personal recreation. IMO the attack from the French authority on “cost shared flight”, is not so out of line as many here seems to think.
Anyone at Oshkosh this year? We’re on the WACO stand…!
