You Know Nothing About Seatbelts - Part 2
A Seatbelt’s Job Goes Beyond The Crash
Think your seatbelt only helps you when the metal hits the dirt? Nope. The magic of seatbelts goes far beyond the prevention of injuries and fatalities during actual impacts. Seatbelts also help the plane fly better and move more safely during maneuvers, sometimes preventing that impact from even occurring.
The first way seatbelts do this is by helping to moderate the weight and balance of the aircraft. Limiting the numbers of jumpers on board to the number of seatbelts limits the risk of overloading the plane, which we all know is a bad scene (slower acceleration, sloth-like climb, stall danger due to higher stall speed, and the like). It also keeps the wiggly weight of the passengers pinned in place, helping the pilot maintain control.
Take an example. One day, a Cessna 205 aircraft ran out of fuel just after takeoff from Celina, Ohio. (Everyone on board--the pilot and five parachutists--perished in the incident, so witness reports and NTSB investigation reports are all we have to explain what happened.) DiverDriver.com explains that, of the witnesses that reported hearing the airplane during climbout, each “described smooth engine noise, brief ‘sputtering,’ and then a total loss of engine power. The airplane descended straight ahead at the same pitch attitude, then the nose dropped, a parachutist exited, and the airplane entered a spiraling descent.” That first jumper left from the student position--as the door was under the wing and not in the rear like the Cessna U206. His exit abruptly shifted the weight aft, rendering the aircraft uncontrollable. Two more jumpers attempted to exit. The all three jumpers who exited the aircraft were unable to deploy parachutes. Everyone left in the aircraft perished in the violent resulting crash.
Another sacred duty of the seat belt: to help the pilot maintain precious, tenuous drabs of control during violent maneuvers in the lower end of the altitude spectrum. Belts hold skydivers in place during the top-gun shit that pilots have to pull sometimes in order to avoid mid-air-collisions, stopping meat from rattling around the cabin and coming down unbalanced.
Note: As skydivers. we’re at pretty serious risk for these, because this kind of incident is statistically most likely to happen in the crowded, lackadaisically-controlled airspace around the small airports we tend to frequent.
When two planes go head-to-head, pilots are taught to pull power and dive to the right--which slams un-belted jumpers right up into the ceiling. The landing is a mystery, but if too many of them land too far aft, the airplane will be unbalanced, stall and spin. Whee. Ugh.
“Sure,” you say, “But that shit hardly ever happens.”
In the next installment, we’ll take a look at the long list of recent incidents you haven’t even heard about--and meditate on the totally-coulda-been-you aspect of the thing.
Very good information. Although, if "seatbelts off" alti is reached, off they come. The evasive maneuver, therefore, above seatbelt alti could still have bad results, although, in my opinion, less likely or deadly. A plus information, and I thank you.
Russell M. Webb
TIS 38Y 4M 13D as of Sept 27, 2016.
No pilot is ever taught to "dive to the right" (unless taught incorrectly). Give way to the right per FAR 91.113 right of way rules for approaching head-on - "When aircraft are approaching each other head-on, or nearly so, each pilot of each aircraft shall alter course to the right."
If severe maneuvering was actually a "threat" then the policy for wearing seatbelt would be to take them off just before exit not at 1500ish AGL.
In a perfect world, every pilot would broadcast their intentions, fly predictable patterns and constantly watch for other airplanes, parachutes, balloons, etc.
Perfect pilots keep such good watch that they spot converging traffic more than 3 miles away and gentle alter course to pass on the right or behind the other airplane. These aeronautical courtesies are based on centuries-old sailing maneuvers.
In the real world, "Sunday pilots" do not always fly predictable patterns, so the later you spot them, the more violent the maneuvers to avoid collision.
"His exit abruptly shifted the weight aft, rendering the aircraft uncontrollable" What B.S. Either you would have to show that the aircraft was already very poorly loaded with an aft CofG -- or else every jump operation with a C-182 would crash (or front door 205/206). And the nose had already dropped. So either the plane was already starting to stall, or the pilot mishandled the plane and didn't get the nose down enough when the engine died.
And what are you arguing about seat belts? Do we even know if they had belts on or not during the climb out? So why is the crash being used for saying that seatbelts prevent movement in flight? The description never mentions the aircraft pitching up, so even if they were unbelted, what does the crash have to do with your idea of having seatbelts keep jumpers from moving about?
As for "Sacred duty" of the seatbelt to keep people from bouncing around during evasive maneuvers? Hardly. It's a very rare occurrence. If it were important, then you would have to argue that we should keep seatbelts on at all times until jump run, or at least above the 1000' or 1500' typically used now, completely contrary to current practice. You could well argue that, but didn't. So which is it? How often do pilots really do "top gun shit" when flying jumpers?
Besides, you've been in skydiving planes -- You could bounce around a whole heck of a lot with a typical belt, though at least in a large cabin aircraft not everyone would end up at one end or other.
"Dive to the right"? Nothing like this is ever taught. A pilot is more likely to apply sudden positive G during a rapid turn.
I await your expanding on the "au contraire" thoughts about seatbelts in flight. Maybe you have examples.
While you have undoubted skills in different areas, and have the ability to write, your flippant "know it all" writing style has become annoying. That's more personal preference -- Others may like it. It sometimes makes it look like there are simple easy answers to everything, and you're here to enlighten us all to the one true way. But when facts and interpretations are tricky, slow down that writing of yours -- you might whip out a nice sounding paragraph really quickly -- but saddle it with some debatable advice -- so think through it all more.
Mind you, Part 1 of your series seemed quite reasonable, with a decent review of the history of the seatbelt issue!
pchapman Yes, the Celina, OH Cessna 205 crash DID show that the aircraft was over loaded and out of aft CG for takeoff. But it did fly. The NTSB calculated not only the CG for takeoff but also what the effect of the jumper leaving the front would do. It put it FURTHER aft of the CG limit rendering the aircraft uncontrollable. I know you'd like to think it was just a pilot screw up but you have to look at the totality of the accident. It's not just one thing. Running out of gas on takeoff lead to the engine failure. But engine failures don't mean death! So why did he lose control? CG.
WHICH IS THE EXACT POINT OF THIS ARTICLE.
From the NTSB:
"The operator provided weight and balance information, individual occupant weights, and a seating plan for the accident flight. The maximum gross weight for the airplane was 3,300 pounds and the aft center-of-gravity (cg) limit was 47.27 inches aft of datum.
Weight and balance figures for the accident flight were computed at a fuel weight of 60 pounds. Preliminary calculations revealed the airplane weighed 3,060 pounds with the cg at 48.30 inches aft of datum.
A weight and balance was also computed using the same figures, minus the first parachutist that departed the airplane. The calculations revealed the airplane weight to be about 2,898 pounds, and the cg 48.76 inches aft of datum."
Why is it being used to show seatbelts prevent movement in flight? Well, sir, if they had seatbelts on they couldn't have moved to get out! Thus preventing the inadvertent stall/spin entry after engine failure. They were below 1,000 feet AGL.
A witness statement: "The plane came straight down. There was no forward motion. He had all that field in front of him. Why in the heck he didn't get the nose down, I don't know."
And a personal tale if you'll indulge me. I was a jumper in a 206. We all took our seatbelts off at 1k like every one ever did. The pilot had no instrument rating and I didn't expect her to fly into clouds. But I always wore my helmet the entire flight to altitude. Well, the pilot entered a cloud on climb and panicked. She shoved the controls forward and all of us unbelted jumpers went to the ceiling. She came out of the bottom of the cloud and saw we were diving. She pulled back and we slammed to the floor. This sudden weight slamming the floor caused the plane to pitch up sharply and re-enter the cloud. She shoved again and we went to the ceiling. We went floor to ceiling to floor three times before recovering. Had we been belted in still the loss of control would have been less severe if not all together absent due to load shift. I was the only jumper who didn't injure their head. So yah, maybe we should be considering wearing seatbelts to a higher altitude like just before gear checks happen before exit. Why take them off at 1k? If you can't get out of the restraint quickly then it was improperly worn.
I'd just like to say that @diverdriver is my f'in hero, and that every skydiver should pop over to diverdriver.com and have a look. You're gonna be like WHOA I DID NOT KNOW THAT, and you're going to be glad you do now.
diverdriver, I had simliar youngster pilot go into cloud, nose down, and he froze once we came out diving straight down.
Another jumper actually, from the ceiling, pulled the yolk back. If we had seatbelts on, I doubt anybody would have survived the flight. Negative G on a seatblet......Pilot error though, but has relevance to wearing seatbelts, or in this case not.
To me, it is up to the pilot to make the call, he/she is in charge or the plane, and also in charge of CG. I would personally prefer a more forward CG then aft, purely cause I like speed, and speed equals more lift.
I disagree with some statements, but keep them coming Nette.
More articles in this category:
- You Know Nothing About Seatbelts - Part 4 - by Annette O'Neil (Posted: 2016-10-18)
- You Know Nothing About Seatbelts - Part 3 - by Annette O'Neil (Posted: 2016-10-04)
- You Know Nothing About Seatbelts - Part 2 - by Annette O'Neil (Posted: 2016-09-27)
- You Know Nothing About Seatbelts - Part 1 - by Annette O'Neil (Posted: 2016-09-20)
- How To Be A Good Passenger in a Jump Plane - by Gary Peek (Posted: 2003-08-21)