Eight Skydivers Die in Plane Crash in Finland

[Edi]

On Saturday during Easter, eight skydivers died in Finland when the plane (Comp Air 8 ) that was ferrying them up for a jump developed engine trouble and subsequently (for a possibly unrelated reason) also lost control and fell to the ground like a brick. Of the 11 people on board, only three survived, the pilot and two jumpers. They managed bail out through the pilot's door, while the jump door stayed closed, impossible to open due to the G-forces in the spinning plane. This has been the biggest civil aviation accident in decades here, so it has been getting a lot of press. Rather few articles in English, but here is the best one I could find:

Wall Street Journal

Eight Parachutists Killed in Plane Crash in Finland
Accident Happened Over Popular Skydiving Site About 150 Miles by Road From Helsinki

By
Juhana Rossi
Updated April 20, 2014 3:13 p.m. ET

HELSINKI—Police and investigators said eight parachutists died when a light utility aircraft suddenly fell from the sky over a popular skydiving site Sunday in Jamijarvi, a small town in Western Finland some 150 miles by road from Helsinki.

Three people, the pilot among them, managed to bail out with their parachutes from the aircraft and survived with only minor injuries.

"By Finnish standards, this is the most serious flight accident in decades," said Ismo Aaltonen, an investigator with Finland's Safety Investigation Authority.

Mr. Aaltonen was speaking in a joint news conference held by police and rescue services at the site of accident. The news conference was broadcast online.

According to information gathered by the police, the aircraft was traveling at a relatively high altitude of more than 10,000 feet before it plunged toward the ground.

Eyewitnesses "saw three parachutes detach from the plane which then came down in a steep angle," said Pentti Lehtimaki, an inspector with the local police service. The authorities gave no tentative theory for the cause of the accident. It was also unknown if the pilot had communicated the plane's distress before its fatal dive.

Investigators are now looking into eyewitness reports that claim some objects or aircraft parts fell away from the plane in its final moments on the sky.

The aircraft involved in the accident was an American-made Comp Air 8. Comp Air 8s are so-called homebuilt aircraft that are typically assembled from kits by people active in general aviation.

The rescue authorities said the wreckage was severely damaged because it burned after it had impacted with the ground. The police haven't identified the individual crash victims, but according to tentative information they are experienced sky divers from the city of Tampere, some 50 miles east from the accident site.

According to media reports and its Facebook site, a Tampere-based skydiving club was holding its annual "Easter Boogie" sky diving event at Jämijärvi over the Easter holiday weekend, which in Finland extends until Monday.

Write to Juhana Rossi at juhana.rossi@wsj.com

This Finnish language article from MTV (a Finnish media company, not Music Television) has a cell phone video capture of the crash by one eyewitness, which shows rather clearly why so few people managed to get out. The plane burned almost completely on impact, so investigation of the crash is very difficult due to lack or surviving recordings from the wreckage.

[Broomstick]

I heard of that through the aviation grapevine. Unfortunately, the video won't run on my system, but from descriptions it sounds like after the engine problem they might have slowed down too much and then entered a spin. The g-forces even in a controlled spin can be significant, in an uncontrolled one, possibly with the center of gravity shifting due to people moving inside the aircraft, well... it's Not Good.

It is entirely possible that the g-forces built up to the point it started to pull the aircraft apart.

My condolences to all concerned.

[Wicked Pilot]

Assuming it was just an engine failure that started it off, no one should have lost their lives over this. It should have been ten jumpers under canopy and one pilot in a big glider toughing down in a field somewhere.

[Broomstick]

Have you seen the average jump plane, Wicked? Usually the seats are pulled out and the skydivers jammed inside, unsecured. It is possible for the passengers to slide if the attitude becomes extreme enough which could knock the CG all to hell. It's not supposed to happen that way, but it can.

[Edi]

One of the things that has been said in Finnish media is that right after engine failure, the plane also lost pitch control due to the failure of some mechanism, went into an overly steep nosedive and right after that into an uncontrolled spin and crashed.

It had been slated to do twenty sorties that day and this fatal one was at the halfway mark. The pilot was an experienced veteran of the skydiving scene. The Tampere Skydiving Club requires their pilots to have a minimum of 500 flight hours under their belt before they let them in the controls of their jump planes and this guy had a lot more. It was the pilot who made the call to abandon the craft, but it was the G-forces that made it impossible for most of them to get out.

[Wicked Pilot]

Have you seen the average jump plane, Wicked? Usually the seats are pulled out and the skydivers jammed inside, unsecured. It is possible for the passengers to slide if the attitude becomes extreme enough which could knock the CG all to hell. It's not supposed to happen that way, but it can.

I've dropped many hundreds of paratroopers from my aircraft over the course of my career. But to answer your question, no, never seen the inside of an average jump plane. I realize the CG issue you bring up, and agree that it's not suppose to happen that way. Engine failure at altitude should equal nose down, pitch for best glide, get the jumpers out if they're over a suitable area.

One of the things that has been said in Finnish media is that right after engine failure, the plane also lost pitch control due to the failure of some mechanism, went into an overly steep nosedive and right after that into an uncontrolled spin and crashed.

How would an engine failure in this type of plane would lead to uncontrollable pitch? That's a head scratcher, for me at least.

[Broomstick]

The Comp 8 is a kit built airplane. That means the soundness of the construction is going to vary from one to another depending on who assembled it. I don't know the certification regulations for such airplanes in Finland, I do have some notion of them in the US. Some kit-built planes are just fine, arguably even better than some factory built airplanes, but others can be very questionable. So we don't know how sound the airplane was to start.

Second, with all due respect to Wicked's military career, military jumps and civilian jumps can be quite different in many respects. There's the old question "Why would you jump out of a perfectly good airplane?" but upon seeing civilian jump planes I realized they were not, by and large, "perfectly good". Some of them are pretty damn rickety, to be honest. I think in recent years there have been more skydivers killed in the airplane going up than on the way down under parachute. Maintenance can be spotty and, since everyone on board (including pilots) typically do wear parachutes perhaps there is over-reliance on the notion of there being an alternate way to get back to the ground, at least with some participants. There are skydive operations that are conscientious about aircraft maintenance but I have seen some jump planes that frankly I don't regard as safe.

As designed, a Comp 8 carries 7 passengers and 1 pilot (hence the 8 in the name). On this trip, there were 11 aboard. While you can increase people capacity to some degree by taking out the seats and having the skydivers pack in on the floor you are already departing from the original design by doing so. It is possible that it was overloaded.

So, you have an airplane that may or may not by properly built, which may be overloaded, there might be maintenance issues (something that needs to be looked at in any accident) and certainly had departed from the intended seating plan of the designers. If the CG is aft then a working engine might compensate for it but if the engine fails and the wing stalls (which may happen sooner than expected under these conditions) then recovery may be either much more difficult or even impossible.

Of course, I will take the word of proper Finnish aviation authorities investigating the crash over what the media reports. I'm just saying, it's not unheard of for jump planes to be overloaded, out of balance, and prone to load shifting. The man who gave me my first intro ride was also a skydiver and was once on a mass jump where Something Went Wrong and the upshot was most of the jumpers left and the reminder were plastered to the walls of a spinning airplane. In that case the problem was resolved safely, but the abrupt and unplanned departure of the bulk of the "cargo" in an uncontrolled manner did result in some very bad weight and balance problems. In other words, it's not an unprecedented scenario. It's not a disciplined military operation, it's a bunch of civilians who may or may not panic in an emergency.

It could be something as stupid as a broken control cable, which would certainly play merry hell with the pitch control. Why would a control cable break just after an engine failure? I don't know. If something flew off the engine I suppose it could sever or jam a cable, but I'd think the pilot would notice that. Maybe he did, maybe he didn't, we don't have enough information to go on here. This is assuming the Comp 8 uses mechanical cable linkages, which is the usual practice on an aircraft in that size range, but the Ikarus I few a few years ago, although using control cables, also used a sort of "fly by wire" for trim control instead of a direct linkage. That's the thing with some of the newer and/or kit planes, you have to be careful about assumptions based on Cessnas and Pipers from the mid-20th Century being so damn common and the "default" most pilots think of.

[Edi]

The regulations on kit-built planes and their construction oversight are fairly stringent here. This particular plane had actually had two people do the initial inspection rather than just the normal one because of the safety reasons and the relative complexity of the project.

One of the mechanics who was part of the initial inspection has said that the most probable cause is either overload or a major structural failure (wing snapping in two being the most probable of these). It's early days yet and the investigation may take up to a year, so this will probably not wrap up too quickly. There may be multiple factors at work, so why there may have been engine trouble in addition to everything else, it may not be the cause.

The pilot has told of the engine sound going from normal to a discordant rattling and clanging a few moments before the accident, so an engine breaking and a fragment cutting a control cable is not at all outside the realm of possibility.

I'll post updates as soon as there is anything solid. The investigation boards in cases like these are usually pretty good about giving out relevant information and statements to the public.

[cosmicalstorm]

A shame they were locked inside. I jumped twice but never had the guts to finish the jumpclass. Part of the reason was the tunacan-like conditions inside the small plane we jumped from.
When I was preparing for my third jump a guy crashed while swooping a short distance away from me. He shows up on Swedish TV occasionally due to a conflict with the healthcare-system that he is fighting from his wheelchair.

[Broomstick]

I finally found a copy of the video that would play on my machine. It doesn't show the start of the problem, but the airplane very clearly was in a fully developed spin that was flattening out as it descended. That means the situation was getting worse, not better. That's all that can be said with certainty at this point. Whatever the initial cause, the airplane did stall at some point and with the pilot gone presumably there was no one aboard to recover, if that was even possible at that point.

[Broomstick]

I jumped twice but never had the guts to finish the jumpclass.

I remember the thread where you discussed this. I disagree with your self-evaluation. It wasn't a matter of having "guts", you made a decision that the potential benefits of continuing weren't worth the risks to you, personally. That's called making a go/no-go decision. I respect your decision to stop as much as I would have respected a decision to continue.