Randy Haskin wrote:
I know we have spoken on WIX before about ejection seats, and the perception that a lot of people have about both their capabilities and their use.
Just so it doesn't get to this, let's dispel a couple myths right from the beginning:
First, they're not a magic guarantee of safety. All ejection seats have a performance envelope in which conditions have to be met in order for the system to function and the occupant to achieve a chute opening. Initiating ejection out of that envelope statistically means that the ejection will not be successful, resulting in injury or death. Some modern seats have incredibly wide envelopes, but even those seats have their limitations (especially when it comes to vectors downward when initiating ejection). Even successful in-the-envelope ejections can result in serious injuries, like back or neck compressions or broken/missing limbs due to flailing injuries.
Second, pilots don't see ejection seats as an easy alternative to get out of a jam. In fact, the number one reason for fatalities in ejection seat aircraft is "a delayed decision to eject". For a whole host of reasons it would take pages to discuss, pilots would rather try and stick with the airplane to solve a problem, rather than pull the handles and admit failure. And, no, these decisions are not "he stuck with the aircraft to he could keep from hitting people on the ground." If someone has the ability to steer the aircraft away from people on the ground, they wouldn't have a reason to eject in the first place (e.g. they'd still have control of the airplane and its energy).
So, without speculating on the reasons for this mishap, this is something I've posted in a couple places on the internet today. The real issue with this crash and the Weber ejection seats in the Tudor is sink rate. The ejection mins for the seat are something in the neighborhood of 100kts and 200' AGL, and with *no* sink rate.
When I was flying T-37s (which had essentially the same Weber seats as the Tudor) one of our big debates was always at what point when flying in the traffic pattern did we no longer have the option to eject should there be something like a dual engine failure (like hitting birds, etc). The answer was, once you were headed downhill at pattern altitudes, the sink rate was more than the seat could overcome and ensure seat separation and chute opening. Basically, once you rolled off the perch (turned base and final), you were stuck with the airplane no matter what problem you encountered.
What you were supposed to do for a successful ejection is "zoom and boom"....once you had an engine failure, use your kinetic energy to get into an upward trajectory (zoom) and pull the handles (boom!) before the airplane started heading toward the ground, as that was the most likely conditions for a successful ejection.
This crash is a graphic display of the limitations of those seats.
Randy, thank you for this sober and informational post. You answered the only real question I had about the seats in the Tutor - namely, whether they were "zero/zero". I do wonder, would a "zero/zero" seat have increased Capt. Casey's survival chances in this scenario?
This accident is an awful reminder that no matter how professional and experienced you are, even if you do EVERYTHING right, things can still end in tragedy.
Lynn
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