NTSB and Skydiving

Both were -20's from the NTSB info.
As has been mentioned, given engine, atmospheric conditions, weight etc. we don't know for sure that the airplane would have been able to keep flying with perfect flying skill. However, the NTSB says the plane reached perhaps 150' which is out of ground effect. When you lose an engine down low, you have your hands full.

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Advertising is all BS with a lot of latitude for creative license.

You and I may know that. But does the general public? Not likely; if they did then lots of people working in advertising would be out of a job.

Like it or not (note: I don't like it), the perceptions of the general public are what matters here, not what we as skydivers think. By selling skydiving as a thrill ride, we are giving the impression to the general public that the entire "experience" is safe.

Do you think the NTSB would have held that meeting and made these recommendations if it were only experienced skydivers and pilots that died in those aircraft accidents?

I still find it "odd" that there was no fire following the 203E crash (given the high level of violence of the impact) and have been wondering all along if this would have been commented on (the lack of a post crash fire) in any way in the final report. Apparently, this hasn't been touched on in the NTSBs/FAAs investigation? I guess it was just "luck" that a fire didn't happen. I'd imagine there would have been no survivors if one had. I suppose all the lawsuits are still in the process of playing out too?

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This one is starting to irk me more and more... probably should have concerned me more in the past... folks not belting themselves in or not belting their helmets in if they choose not to wear them for takeoff AND getting pissy if someone on the load asks them to put their belt on and/or belt their helmet in if they're not wearing it because the thing could turn into a projectile in a crash, if not. Evidently the Perris Crash and the Sullivan Crash wasn't enough to teach us this?

And you are suprised? I have experienced this directly myself.

If there was no FAA rule to wear seatbelts then a large percentage of skydivers wouldn't use them despite all evidence supporting their use.

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you will continue to turn until either you encounter the ground or you can get airspeed above Vmc.

Or until the pilot decides to reduce power on the good engine, rather then pushing it up trying to climb.

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I still find it "odd" that there was no fire following the 203E crash (given the high level of violence of the impact) and have been wondering all along if this would have been commented on (the lack of a post crash fire) in any way in the final report. Apparently, this hasn't been touched on in the NTSBs/FAAs investigation? I guess it was just "luck" that a fire didn't happen. I'd imagine there would have been no survivors if one had. I suppose all the lawsuits are still in the process of playing out too?

IIRC Chris told me something about the fuel tanks not being in the wings on an Otter. Might have something to do with it.

Yes, the fuel tanks in a Twin Otter are not in the wings, rather they're in the belly, but did you see the state 203E was in (pics) after the crash? I still find it amazing that no fuel meet an ignition source. The lack of a fire following the 203E crash made me wonder about the amount of fuel on-board or if BOTH engines were shut-down prior to impact... but that all seems to be mox-nix at this point.

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And you are suprised?

Unfortunately, "No", not really.

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USPA is aware of next Tuesday’s NTSB hearing on two subjects, the July 2006 Missouri Twin Otter crash, and the Special Investigation on Parachute Operations. USPA officials will be there, and we’ll report soon afterward on the results of the hearing, either on the USPA news page, the USPA blog, or most likely both.

- Ed Scott, USPA Executive Director

oh, we know how you like to give us all information you have available... ...

I think I am leaning towards this being a possible good thing. If skydiving aircraft is kept up to date, and safe, then the owners should not be worried.

Go fill up a container (small cup open lid) with Jet-A and take your lighter to it and see if you can get it to burn. After that get you a misting spray type container and find a way to add flame to the mist of fuel and see what happens.

That type of fuel don;t burn like or explode like other fuel types, it takes more for ignition, such as a fine mist of fuel or even vapor (TWA flight 800) but puddles or streams running out of a broken fuel tank take more to set it off and it won't explode like 100LL or 87Oct.

That said it will still burn.

Yeah, yeah, I know all that, Strat.

On one hand, if I was sitting next to an open bucket full of Jet-A or JP8 and you said I had to sit there while you tossed a lit match into it, I would be not so much worried, as opposed to if it was a bucket of gasoline.

On the other hand, would you want to stand in a puddle of JetA and toss a bucket of the stuff on a hot PT6 that just got riped from its mounts?

Anyway, glad a fire didn't break out in the aftermath of the 203E crash; still find it strange it didn't, but like the ol' saying goes, "rather be lucky than good any day".

There seems to be a huge misconseption about the term ON CONDITION. Whether you're Part 91, 135 or 121 you may operated ON CONDITION if specific criteria is met. Under 135 & 121 this criteria includes being on an Approved Program, regular Hot Section Inspections or Borescopes, Trend Monitoring, Overhauling components (i.e. Fuel Controls, etc) at their TBOs and your engines have to meet specific performance criteria as found in the AFM's Performance Section and Maintenance Manuals.
Under Part 91 the only thing that is the same as 135 or 121 is that the engine(s) need to meet the Performance criteria. This applies to Piston aircraft also.
Most operators are under the impression that if the engine(s) start, the aircraft can take-off and climb to altitude, then you're good to go. Not so.
For example using a Twin Otter:
Your operating on a hot, humid day. The pilot looks in the AFM to find the engine performance expected for that day on take-off. The pilot finds that he can expect a take-off torque of 46 psi instead of the 50 from the -27s. He taxis down for take-off, pulls on to the runway, advances the power levers, starts his roll and takes off. He only got 42 pounds of torque on one engine because it was temperature limted, the other was 47.
This means that the one engine did not meet the performance standards to be ON CONDITION.
Now this could have been a one time thing. It may be corrected by doing a simple Compressor Wash or may be the engine is out of rig. If it happens on a reoccuring basis then that definitly means that the engine does not meet the criteria for ON CONDITION and it is not airworthy.
Also, if you look at Pratt & Whitney's PT6A Service Bulletin concerning TBOs and extensions, Pratt will not approve an ON CONDITION program for engines used on skydiving aircraft do to the way they are operated. It does state, though, that for ALL operators an engine MUST BE overhauled after accumilating 12,000 hours.
The loop hole for skydiving operators is the way Part 91 is worded.
It is my belief that the FAA may not hold operators to TBOs, but if the want to operate ON CONDITION they are going to have to do so under an Approved Program.

Many errors and I don't have time to go through them all.

It's not Vmc. It's Vyse (best rate single engine to climb). Vmc is minimal control speed which is less than Vyse. The pilot got below Vyse and couldn't climb. Vmc is lower at lower weights. It is indicated by a red line on the airspeed indicator for MAX GROSS T/O WEIGHT. Vyse is a blue line.

The propellors don't rotate left. They rotate clockwise as seen from behind. The descending blade creates more thrust than the ascending blade creating what we call "P-Factor". The distance on the right engine to the center of max thrust is longer on the right than the left. Thus being the left engine is the "critical engine". But in this case the right engine failed so not worst case.

I've never heard of -21 engines. There are -20. Max thrust at Sea Level standard day is 550 Shaft Horsepower. The Density altitude on that day was much higher.

The pilot did a rolling takeoff using only half the runway. He put himself in the corner and couldn't get out. I will write a longer post of what I think happened on that Sullivan crash but I don't have time at the moment. Just couldn't let some of these errors go further.

Hey Chris;
A -21 is basically a -27 derated to 550 hp fo use on early King Airs. I'am not quite sure how it was derated, but its not like a -34 install on a Twin where the derating factor is the red line on the torque gage.
Not to many left in service.

Some helpful numbers regarding PT6 variations:


http://en.wikipedia.org/wiki/Pratt_&_Whitney_Canada_PT6

Hey guys and gals, don't take my word on the whole -21 engine thing. When I think about it, they may very well have been -20s and not -21s. Like I said earlier, I really am not an engine expert on this sort of thing and have myself just started learning and trying to educate myself on how these things work. I'm sorry if I confused anyone.

I am still trying to understand how it all happened. I have heard all of these terms and most of them are a different language to a layman. Things like hot sections, VMC, Vyse, "the P factor",V1, V2... I am starting to get it more but still don't understand exactly what happened.

What I do understand is that Scott made a mistake to take off short field and not utilize the entire runway for an out. OK. I can see that. I have been on many short field take offs in that otter and never understood them myself but figured there was a good reason for it. My guess was always to save fuel?

There was mention of Scott not keeping up his airspeed on the left engine as a pilot error. But then I heard that a -20 or -21 whatever it was, was unable to climb in an ambient temperature that exceeded 80 some odd degrees. Then there was mention of air density and I still don't really get what that is. Is air density like humidity or how much air is in a given area??? And, how does it affect aircraft performance? Sorry to sound dumb.

I am also still unclear on the whole spinning prop blades that "came off", "burnt off", direction of spin or how that causes things to happen. So I tend to have a hard time explaining or grappling with what seems to be ignorance in engine mechanics of airplanes.

I'm hoping Chris S. will have a couple minutes to help me out here with some simpler explanations. Did the prop blades sever and enter the hot section of the engine causing the fire?

I also heard that there not being a fire on the ground was evidence that Scott did the right thing and shut that engine down immediately. I am sure that since the engine was on fire not even 50 feet off the ground that is evidence that Scott was doing something right.

Since I am not a pilot or a mechanic, I am sure I will have to go and reread several times the whole prop direction of turn in relation to engine failure, feathering (what does that mean vs. shutting it down), countering the planes yaw by increasing speed with the other engine???

I think skydivers should understand more about this. I feel like I need to understand more. I was thinking about it the other day. Being a rigger, I kind of understand what it means when someone comes up to me and asks me to pack their reserve parachute. I know how much skydivers place importance and trust in their rigger. But statistically, when you think about it, you only need your rigger when you need your reserve. Your chances are small if you can pack your main decently enough. Your need for your pilot and your aircraft are immediate and necessary on every jump.

Totter,

With regard to the engine "life" or what is considered to be under the manufacturers warranty for airworthyness... Is it true that let's say a -20 has a life expectancy of 30,000 hours. If you make modifications to that engine lets say with newer parts or something, can the life be extended? Is there gray area there or is it cut and dry?

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Aviation Report - On July 29, 2006, a de Havilland DHC-6-100, N203E, operated by Skydive Quantum Leap as a parachute operations flight, crash after takeoff from Sullivan Regional Airport, near Sullivan, Missouri. The pilot and five parachutists were killed. Two parachutists were seriously injured. Media Contact: Terry Williams

So is the Final Report out yet on the 203E crash? Then NTSB website still only has the Factual.

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Also suggested that people not wearing their restraints may have caused the death of other occupants.

This one is starting to irk me more and more... probably should have concerned me more in the past... folks not belting themselves in or not belting their helmets in if they choose not to wear them for takeoff AND getting pissy if someone on the load asks them to put their belt on and/or belt their helmet in if they're not wearing it because the thing could turn into a projectile in a crash, if not. Evidently the Perris Crash and the Sullivan Crash wasn't enough to teach us this?

Hey Zigzag,

After reading this, I wanted to respond. I am not sure if you are referring to Quantum Leapers and Perris people as not wearing their seatbelts. I have often wondered myself while sitting on an airplane, just how much is this belt going to help me out in a crash situation? Apparently, in ours not too much because they failed. I was reading the article which stated the FAA may begin to adopt a direction toward greater safety restraints that are dual. I don't know what happened with the safety belts in the Perris crash but if they are failing us I think something needs to be done if it can help save lives. Driving laws require us to wear seat belts more than likely based on statistics and evidence to show there is a benefit in lives saved. I think it is a good time for the FAA to regulate jump planes if we are unable to regulate them ourselves to make sure if we are going to go through the trouble of wearing them that they are going to do their job. I don't know how much they would have helped in the QL crash. Many of our friends were dead on impact which sucks. A couple survived long enough to make it to the hospital. One made it through all of that but his quality of life deteriorated so rapidly that he is no longer with us.

Could a seat belt have made a difference in Steve's life? Possibly... I can see as the videographer strapped to the tail of the plane he may have just been able to hang instead of impact, who knows but I think if we have to wear em they should have to work.

Basically a turbine engine, if it is maintained properly and overhauled at some given interval, will run forever. I know of PT6s that have over 100,000 total hours on them.
Rebuilding an engine by repair does not constitute an overhaul. There are different specifications for each that are way to numerous to mention here.
Let me be specific on this MANDATORY 12,000 hour TBO. This is, if the engine is new once it reaches 12,000 hours it must be overhauled, or once it accumilates 12,000 hours after its last overhaul.
The PT6 class of engines are very reliable and if they are taken care of they will last forever.

NoShit,

Good thoughts.

In my lay opinion, given the violence of the 203E crash... enough to break both engines / wings off, crush the cockpit back ?? feet and break the tail off... I'd pose that for the unfortunate occupants, 3-point or even 5-point seat belts/harnesses may not have made a difference or may have only made enough of a difference to survive, but be horribly injured and crippled... again, caveat, just my lay opinion. Of course, that's not a reason not to try, just trying to state a bit of realism to the task. Seems the real problems were the initial failure of the right engine, followed by the pilot's inability to maintain controlled flight.

As for the Perris crash... I'll have to caveat that too as it was slightly before my time, but from what I understand (and I'd be glad to be corrected by someone who does know better if I understand incorrectly)... but from what I understand there, this was another very violent impact, not a controlled forced landing, violent enough to break the back of the airplane and shear the wings off and the seat-belt factor there was at that time, there were no benches, jumpers just sat on the floor facing aft with belts on the floor fastened (or not fastened... speculation) across their laps... upon impact everyone on board wound up in a pile of bodies in the front of the plane up against the bulkhead which separates the cabin from the cockpit of a twin otter.

Again, in my lay opinion, in a less violent impact, say one where its a controlled forced landing, then it would be hard to argue that having a currently configured seat belt/bench that one would see in a typical jump Otter fastened correctly about you would be better than not having a seat belt on at all... and having your hard helmet / camera belted in too, if not on your head, would be better than just holding it in your lap.

Anyway, just some of my thoughts.

If / How this suggestion that jumpers should have more than just a lap belt, but a 3-point restraint, plays out will be interesting, if nothing else.

Seatbelts/restraints: Jumpers on 203E did not use the belts installed properly or at all. They were fastened but not sinched. This allowed people to travel forward into the crush zone. One jumper at least was not belted in and travelled forward striking people. Same as in the Perris 1992 Twin Otter crash. The people in the back of the plane used (unwillingly) the people in the front as cushions from impact.

NoShit: I think you are confusing prop blades with turbine (engine) blades. Turboprops are mini jet engines hooked to propellors for thrust. So there are many baldes to discuss. The compressor (first part of the engine) has a seires of blades that as it turns it compresses the air getting it ready for fuel to be added. From the photos I saw it looks like the compressor began to fail on the takeoff roll. There was so little runway to use AND because the pilot did a rolling start instead of insuring both engines ran up and stabailized I feel he was focussed with the end of pavement. A PT-6 engine requires a push up of power and pause to allow the compressor overpressure relief valves to close. The engine is very efficient and at idle it's too efficient for stages of the engine to take that air. So it dumps it. This is why doing a rolling takeoff on such a short runway even if considered "light" on the takeoff weight was an action that put him in a corner.

Now, give that it was a hot day (high density altitude). The airplane "acts" as though it is taking off from a higher elevation than it physically is. Dash 20/21 engines are not well known for their ability to produce full power on hot days. This is why you see operators converting to -27/-28/-34s. They want to produce the max allowable power at even high temperatures.

Vmc (Speed: minimal control) This speed is marked as a redline on the low end of the airspeed indicator. It signifies to the pilot the minimum speed at full gross (allowable) takeoff weight (loaded with an aft CG) with the critical engine failed (in the case of a twin otter the left engine) that will allow the pilot to maintain directional control (head where he wants to go). THIS DOES NOT MEAN HE WILL BE ABLE TO CLIMB OR MAINTAIN ALTITUDE!! However, redline is not always redline. If you change any of the conditions I noted for its definition the speed will change (usually for the better ie. lower).

Vyse (Speed: best rate of climb single engine) This speed is marked as a blue line on the airspeed indicator. The aircraft can have a bank up to 5 degrees in the direction of the operating engine and will give you the best climb per time OR the minimum sink per time. However, if taught and used properlly you can trade directional control for performance and climb at better than book values assuming engine performance is not less than book.

That brings us back to maintenance. When an engine fails due to poor maintenance and treatment do you think the remaining engine is likely to be any better?

Pilot training: A pilot who is current and takes regular checkrides in a jet DOES NOT MEAN THEY ARE CURRENT AND PREPARED FOR A FAILURE IN A TWIN OTTER (PROP PLANE). A jet that has engines on the tail does not create the type of yaw that a failure in twin prop can/will. No one should think that an airline pilot who flys for your DZ on weekends only is prepared for emergencies in that DZ plane just because they practice in a sim once/twice a year for a jet. YOU MUST PRACTICE EMERGENCIES ASSOCIATED WITH THE PLANE YOU ARE FLYING AT THE TIME. I've been saying it for years that this skydiving industry needs some standard/trackable initial training and RECURRENT training to ensure a high degree of performance. Pay now or pay the high cost later. And some debts can never be repaid.

But I do not agree with "Zing's" assesment of "we're fucked". I think operators who understand what it really takes will have no problem adapting to what's coming. Had we paid attention to this problem years ago and addressed it properly we would not have arrived at an NTSB special report and presentation. I spoke at the USPA BOD meetings at SDC years ago saying if they wanted to promote skydiving more broadly to the public they had better clean up the jump plane accidents. I was received by the sound of crickets. Well, there you go.

Then there was mention of air density and I still don't really get what that is. Is air density like humidity or how much air is in a given area??? And, how does it affect aircraft performance? Sorry to sound dumb. -

Nothing dumb about that. Air density is how tightly the air molecules are packed.

On a cold day an aircraft can get off the ground faster and climb steeper because there is more air flow over the wing.

On a warm day the aircraft requires more runway and a longer takeoff roll because the air is not as dense thus the plane needs more speed to produce the same amount of airflow over the wing.

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One jumper at least was not belted in and travelled forward striking people.

I've been told this was not the case by someone who was involved in the recovery operation. I can't verify the veracity of their comment but I wanted to post that because the NTSB said they weren't wearing belts when in fact the belts failed.

My concern regarding belts is that they don't get tightened properly and in fact, even if they were sinched down, most people I've seen grab belts that are behind them (i.e. to the front of the plane) thus negating somewhat the point of tightening the belts (if they were).

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One jumper at least was not belted in and travelled forward striking people.

I've been told this was not the case by someone who was involved in the recovery operation. I can't verify the veracity of their comment but I wanted to post that because the NTSB said they weren't wearing belts when in fact the belts failed.

My concern regarding belts is that they don't get tightened properly and in fact, even if they were sinched down, most people I've seen grab belts that are behind them (i.e. to the front of the plane) thus negating somewhat the point of tightening the belts (if they were).

The NTSB studied seatbelt use and belts that failed. They noted that at least one had NO restraint indication which means that they weren't wearing a belt that failed. They had no belt at all. Watch the video for yourself.