Required Reading for Helicopter Tour Pilots

Two accident reports that clearly demonstrate how “hot dogging” can get you — and your passengers — dead.

On Wednesday, a Sundance Helicopters AS350 with a pilot and four passengers on board, crashed in the mountains near Boulder City, NV. It was on a “twilight tour” of the Hoover Dam and Lake Mead.

At this point, there’s no speculation about how the accident occurred. But, as usual, the media is dragging all the dirt they can out into the limelight to sensationalize the event and give people potential places to point blaming fingers.

One of the things the media has brought up is another Sundance Helicopters crash that occurred back in September 2003. I was unfamiliar with this crash — it must have occurred before my regular reading of NTSB accident reports began. Unsure whether I was confusing it with another crash, I looked it up today. But no, this was yet another instance of stupid pilot tricks becoming deadly pilot tricks.

I thought it was worth reviewing this case and another I’ve covered in the past and urge pilots to read both of the final reports carefully to see how reckless flying can kill. What’s interesting to me is how similar these two cases are — heck, they even took place within 30 miles of each other.

LAX01MA272: AS350, August 10, 2001, Meadview, AZ

I covered this accident briefly in Part 5 of my “So You Want to Be a Helicopter Pilot” series. Here’s the NTSB summary:

On August 10, 2001, about 1428 mountain standard time, a Eurocopter AS350-B2 helicopter, N169PA, operating as Papillon 34, collided with terrain during an uncontrolled descent about 4 miles east of Meadview, Arizona. The helicopter was operated by Papillon Airways, Inc., as an air tour flight under Code of Federal Regulations 14 (CFR) Part 135. The helicopter was destroyed by impact forces and a postcrash fire. The pilot and five passengers were killed, and the remaining passenger sustained serious injuries. The flight originated from the company terminal at the McCarran International Airport (LAS), Las Vegas, Nevada, about 1245 as a tour of the west Grand Canyon area with a planned stop at a landing site in Quartermaster Canyon. The helicopter departed the landing site about 1400 and stopped at a company fueling facility at the Grand Canyon West Airport (GCW). The helicopter departed the fueling facility at 1420 and was en route to LAS when the accident occurred. Visual meteorological conditions prevailed, and a visual flight rules flight plan was filed.

The pilot had a reasonable amount of experience with nearly 3,000 hours of flight time, all of which was in helicopters. He had CFI and instrument ratings.

The pilot, however, also had a reputation for hot-dogging. From the NTSB report‘s interview with previous passengers:

According to the passengers, once the tour started, the pilot was talking all the time. He was very informative, and they felt he knew his history and geography very well. They went over the Hoover Dam and Lake Mead. About 20 minutes into the flight, the pilot turned his head toward the back and was talking to the passengers as the helicopter flew toward a cliff. The people in the back were trying to get the pilot’s attention and point out that he was flying toward a cliff, but he pretended he did not understand what they were saying, as if this was all being done on purpose. All this time, the pilot was turned around and talking to the passengers in the back seat, while the passengers were all pointing up trying to get him to climb. One witness said she finally picked up the microphone and said, “they are really scared…turn around and pull up the helicopter,” and he did. She could not estimate how far they were from the cliff when the pilot terminated the maneuver.

One of the passengers stated that there were particularly exciting episodes during the tour that were frightening to some of the others. As part of the tour, they flew over a site that was used in the commercial motion picture film Thelma and Louise, and the pilot pointed out the cliff. The pilot stopped for fuel before he landed in the canyon for the picnic lunch. After lunch, no more stops were made. During the return to LAS, the pilot asked if they wanted to know what it was like to drive a car off of a cliff. She stated that they all said “no” to this question; however, he proceeded to fly very fast toward the edge of the cliff and then dove the helicopter as it passed the edge. The passenger reported that it was “frightening and thrilling at the same time but it scared the others to death.”

Both of these incidents — heading directly for a cliff and then diving like Thema and Louise over a cliff — were confirmed in a video tape provided by the passenger.

Crash Site
I don’t think the pilot expected to end up like Thema and Louise, too.

Evidence at the crash site indicated that not only was the helicopter’s engine producing power at the time of impact, but the collective was full up. The debris field was compact, indicating very little forward movement when the helicopter hit the ground. There was no evidence of any mechanical failure immediately before the crash. The NTSB ruled out many accident scenarios based on mechanical malfunctions before concluding:

In the absence of any evidence to indicate a preimpact mechanical malfunction, and given the density altitude, helicopter performance considerations, and virtually all of the signatures evident at the IPI and in the wreckage, the investigation revealed that a probable scenario involves the pilot’s decision to maneuver the helicopter in a flight regime, and in a high density altitude environment, which significantly decreased the helicopter’s performance capability, resulting in a high rate of descent from which the pilot was unable to recover prior to ground impact. Additionally, although no evidence was found to indicate that the pilot had intended on performing a hazardous maneuver, the high rate of descent occurred in proximity to precipitous terrain, which effectively limited remedial options available.

In other words, he most likely performed his Thelma and Louise maneuver, dove off the cliff, and because of high density altitude, was unable to arrest the decent rate before hitting the ground.

LAX03MA292: AS350, September 20, 2003, Grand Canyon West, AZ

This case is a lot worse. I’ll let the NTSB describe what happened briefly:

On September 20, 2003, about 1238 mountain standard time, an Aerospatiale AS350BA helicopter, N270SH, operated by Sundance Helicopters, Inc., crashed into a canyon wall while maneuvering through Descent Canyon, about 1.5 nautical miles east of Grand Canyon West Airport (1G4) in Arizona. The pilot and all six passengers on board were killed, and the helicopter was destroyed by impact forces and postcrash fire. The air tour sightseeing flight was operated under the provisions of 14 Code of Federal Regulations Part 135. Visual meteorological conditions prevailed for the flight, which was operated under visual flight rules on a company flight plan. The helicopter was transporting passengers from a helipad at 1G4 (helipad elevation 4,775 feet mean sea level [msl]) near the upper rim of the Grand Canyon to a helipad designated “the Beach” (elevation 1,300 msl) located next to the Colorado River at the floor of the Grand Canyon.

You need to read the NTSB’s full report to fully understand what happened here. You can download it as a PDF (recommended) or read it online.

The pilot was experienced. He was 44 years old with an ATP certificate for multiengine airplanes and for helicopters. He had CFI and instrument ratings for a variety of aircraft. He’d logged nearly 8,000 hours of flight time, nearly 7,000 of which was in helicopters. He had a clean record with the FAA.

But the pilot had also earned the nickname “Kamikaze” because of the way he flew. (And you can bet your ass that the media is having a field day with that in its coverage of Wednesday’s accident.)

99° Bank Angle
55° Pitch Angle
Two images from the NTSB report, calculating angles based on photographs and videos shot during other flights.

With a great deal of supporting evidence from the pilot’s previous passengers that same day and earlier, as well as photographs taken during flights with the pilot, the NTSB concluded that the pilot had a history of risk-taking behavior. Photographic evidence showed him flying at bank angles exceeding 90° with nose-down attitudes exceeding 50°. It’s estimated that he typically reached speeds up to 140 knots and rates of descent of 2,000 feet per minute.

With passengers on board.

For comparison’s sake, Sundance policy limited bank angles to 30° and pitch angles to 10° — both of which are very reasonable. Other pilots typically flew that portion of the flight at 110 to 120 knots, descending at 1,000 feet per minute.

Yet the report cites one passenger story after another of the pilot diving into the canyon and flying close to canyon walls. One former Sundance employee who had flown with him stated he “flew very close to the canyon wall” and “banked off one wall and then turned the other way, almost upside down.” One passenger claimed that his friend’s wife was screaming throughout the entire descent.

Sundance received at least two formal complaints about the pilot. There’s no evidence that anything was done about the first. The pilot was suspended for a week without pay after the second, but since Sundance was short of pilots, the penalty was never enforced and the pilot continued working with pay.

It should come as no real surprise that the pilot ran out of luck. According to the NTSB, on that September day:

The helicopter’s main rotor blade struck a near-vertical canyon wall in flight. The resulting damage to the main rotor system likely rendered the helicopter uncontrollable, and the helicopter subsequently impacted a canyon wall ledge.

There was a fireball when the helicopter exploded on impact. There wasn’t much wreckage. You can see for yourself; there are photos in the report. I wouldn’t even know it was a helicopter if it weren’t for the arrows pointing out parts.

Probable cause placed the blame on the pilot, as well as Sundance and the FAA:

The National Transportation Safety Board determines that the probable cause of this accident was the pilot’s disregard of safe flying procedures and misjudgment of the helicopter’s proximity to terrain, which resulted in an in-flight collision with a canyon wall. Contributing to the accident was the failure of Sundance Helicopters and the Federal Aviation Administration to provide adequate surveillance of Sundance’s air tour operations in Descent Canyon.

Disregard of safe flying procedures. That’s a bit of an understatement, no?

What We Can Take from This

If you don’t get the message I’m trying to convey here, you probably shouldn’t be flying anything — let alone passengers for hire in a helicopter.

It’s a fact: many of us fly a little nutty once in a while. Maybe low and fast over flat desert terrain. Or maybe threading our way though empty canyons at high speed. Or performing some other maneuver that takes all your attention and can easily turn into a disaster.

But when does “a little nutty” turn into pushing the aircraft beyond company or manufacturer limitations?

And who in their right mind would fly so dangerously with passengers on board?

You?

I hope not.

The point is that flying like a stunt pilot can get you killed. And if there are passengers on board, you’ll kill them, too.

Is that something you want to be remembered for? Do you want to be the subject of another pilot’s blog post about flying like an asshole with passengers on board? Do you want a derogatory nickname like “Kamikaze” brought up by the press eight years after your death when another pilot who works for your company is killed in a crash with his passengers?

How do you think the “Kamikaze” pilot’s family feels about his accident being brought up again? And again?

Think about why these pilots flew the way they did. Were they showing off? Or trying to get a rise out of their passengers?

In both instances, passengers made it clear — verbally, during the flight — that they didn’t want the pilot to fly the way he was. Think about the people pointing to a cliff face or the woman screaming throughout the descent. Why did these pilots treat their passengers with such disrespect? Scare them for no reason? Put their lives in danger? Was this fun for them? When is fun an excuse to risk other people’s lives?

Do you do this? If so, why? When will you stop? When your crash makes a big fireball like the ones in these stories?

Do you understand what I’m trying to say?

Read these accident reports. Two pilots are responsible for the deaths of eleven people with a twelfth person permanently disfigured.

Isn’t that enough to convince you not to fly like an asshole?

I only hope that Wednesday’s accident report isn’t another example for this blog post.

And my thoughts go out to the families of the victims of this stupidity.

Interesting Links, December 8, 2011

Here are links I found interesting on December 8, 2011:

Run-On Landing to Avoid Brown-Out?

Was this really the best decision?

Although I don’t usually comment on accident reports until the Probable Cause is released, this one seems pretty cut-and-dried. It’s also a good discussion topic. And, best of all, no one was hurt — which also leads me to believe that there won’t be many more facts about it published.

Here’s what happened:

The pilot and the border patrol agent had been dispatched to provide aerial support for an on-going border patrol mission. When the pilot realized there would be a delay in time for when they needed to engage in the mission he decided to land in a grass field and sit idle (to conserve fuel) until their assistance was needed. He said he made a run-on landing to avoid creating a brown-out condition. However, as the helicopter touched down and moved forward (approximately 34 feet) it nosed over and the main rotor blades struck the ground. The helicopter subsequently nosed over and traveled another 34 feet before it came to rest on its right side.

I question the decision to do a run-on landing on dirt/grass. (I suspect the pilot is also rethinking that decision right now.) Would it really reduce the amount of dust blown around enough to justify the added risk of forward motion in contact with the ground on a rough surface?

Brown-Out Landing
Military photo by Staff Sgt. Christopher Boitz of a HH-60G Pave Hawk doing a brown-out landing. (A run-on landing would probably be a piece of cake with wheels.)

I’ve landed [too] many times in dusty landing zones. The dust starts to rise about when I get into ground effect. The longer I’m above the ground pulling pitch, the more dust flies — unless it’s just surface dust and not really deep. The key, it seems, is to get the collective full-down as quickly as possible. When you stop pulling pitch, the dust settles.

When I was trained to do run-on landings, I was taught to make a shallow approach at a speed right around ETL and then slowly lower the collective once contact with the ground was made. So not only is pitch pulled during that shallow approach — when you’re close enough to get the dust flying — but it’s not full down for at least a few seconds after making contact. I can’t see how that would reduce the amount of dust on landing. I’ll be the first to admit that I haven’t tested this theory — we always practiced run-on landings on pavement — perhaps a reader can offer some insight from experience?

I’m thinking that a better way to handle this particular landing would be to make a straight in approach to the ground, thus minimizing the amount of time you’re pulling pitch while in ground effect. It would be important to assure that the touchdown spot was appropriate before committing. Then fly it right to the ground and dump the collective as soon as you’re on the ground. This is the way I try to handle my dusty LZ landings, usually to avoid kicking up dust around spectators or taking even more paint off my rotor blades. (Dust is nasty shit; I’ve already had my main rotor blades painted twice in 1,350 hours.) I admit I’ve never landed on dust so thick that true brown-out was possible — although I’ve come pretty close a few times.

What do you think? How would you handle landing at a LZ where brown-out was possible?

Take the Blame for Your Own Mistakes

Stop trying to pin the blame on others when you screw up.

I have to blog this because I’m pretty fired up about it.

This morning, I got an email message from a lawyer looking for an R44 “consultant”, someone who could

…educate us on the practical day to day operations of an R44. As a consultant, we would not reveal your name or association to anyone. We simply need someone to call when we have a question.

The email message provided enough information that I was able to track down the accident report for the accident the lawyer is working on. Although he didn’t say so, he made it pretty obvious that both Robinson Helicopter Company and the maker of the R44 Raven II’s “auxiliary” fuel pump could be targets of a legal action.

I read the accident report. Without going into details — in this instance, I want to protect the identifies of the parties involved — it was a pretty clear case of pilot errors in judgement and execution. As I summed it up in my email response:

The pilot elects to make an off-airport landing at very high density altitude to take a leak, starts to take off, then overreacts to a yellow caution light and tries to perform a run-on landing in rough terrain.

The helicopter rolled over and caught fire. The pilot and passenger were badly burned.

The details of the Full Narrative Probable Cause accident report paint a picture of a low-time private pilot who flies less than 100 hours a year making a very long cross-country flight in mountainous terrain. There’s evidence of poor flight planning and poor fuel management. But most evidence points to poor judgement on the part of the pilot. Nothing was wrong with the helicopter. It performed as expected in the situation it was put into. The pilot simply made a series of bad judgement calls.

How many times have I seen this in accident reports? Too many to count! The vast majority of aviation accidents are caused by pilot error. Period. This case is no different.

Yet there’s a lawyer involved and that means someone’s thinking about a lawsuit.

Sure, why not? Why not blame Robinson for not issuing [yet] another Safety Notice, specifically warning pilots about landing in mountain meadows at more than 10,000 feet density altitude? Why not blame them for allowing cockpit caution lights to illuminate when the pilot is operating close to rough terrain at maximum power? Why not blame them for not forcing pilots to tattoo emergency procedures on the back of their right hand so they can easily consult them during flight? And the pump manufacturer — why not blame them for making pumps that can have low pressure indications that trigger a caution light?

Why in the world would the pilot in command even consider taking the blame for the results of his own poor judgement?

Because it’s the right thing to do? Am I the only person who actually cares about silly things like that?

As I told the lawyer in my email response,

It sickens me that people can’t admit they made a mistake and get on with their lives. It sickens me that lawyers go after deep-pocket manufacturers to squeeze them for money when they are not at fault. Lawsuits like this are hurting our country, destroying small businesses like mine by jacking up expenses for insurance and equipment “improvements” we don’t really need.

Yes, it’s unfortunate that the helicopter crashed and the people inside it were burned. But it isn’t Robinson’s fault. And it isn’t the pump maker’s fault. The pilot needs to understand this and stop thinking about promises of big settlements. He needs to stop trying to blame others for his mistakes.

Do you think they’ll contact me again about being a consultant? Now that would be a bad judgement call indeed.

Note: If you plan to comment on this post, please limit your comments to the topic of inappropriate legal action. I will not approve any comments that attempt to discuss this particular accident or my summary of it. I assure you that my conclusions are fact-based; you can probably find the accident report if you try hard enough and judge for yourself. The last thing I need is for lawyers to start coming after me.

Dangerous Flying: Abrupt Control Inputs

How sloppy flying could get you killed.

Recently, while flying with a 200-hour helicopter pilot, I was startled when he rather abruptly shifted the cyclic to make a turn. I didn’t say anything then because it wasn’t too abrupt (whatever that means). But when he did it again later in the flight with an even more abrupt movement, I spoke up and told him not to do it again.

Understand that we were flying a Robinson R44 Raven II, which has a rather unforgiving semi-rigid rotor system and very long rotor blades. We’re taught — or should be taught — during primary training to use smooth control inputs, especially when working with the cyclic.

I’m not a CFI and I don’t feel that I have the right to tell someone how to fly, but when a pilot does something I believe is dangerous, it’s my duty to speak up. So I did.

The trouble is, I’m not sure if he believes what I told him — that abrupt inputs are dangerous — or if he thinks I was just nitpicking his technique. (I let it go the first time partially because I didn’t want to be seen as a nitpicker.) Since so many pilots seem to read this blog to learn — or at least to get my opinions on things — I thought I’d discuss it here.

What Robinson Says

Section 10 of the R44 II Pilot’s Operating Handbook includes safety tips. Here’s the one that applies:

Avoid abrupt control inputs or accelerated maneuvers, particularly at high speed. These produce high fatigue loads in the dynamic components and could cause a premature and catastrophic failure of a critical component.

What Robinson is saying is that when you make abrupt control inputs you put stress on various aircraft components. They’re likely concerned about the rotor blades, mast, transmission, and control linkages most. This makes perfect sense.

Robinson Safety Notice SN-20, titled “Beware of Demonstration or Initial Training Flights,” includes these statements:

If a student begins to lose control of the aircraft, an experienced fight instructor can easily regain control provided the student does not make any large or abrupt control movements. If, however, the student becomes momentarily confused and makes a sudden large control input in the wrong direction, even the most experienced instructor may not be able to recover control.

And:

Before allowing someone to touch the controls of the aircraft, they must be thoroughly indoctrinated concerning the extreme sensitivity of the controls in a light helicopter. They must be firmly instructed to never make a large or sudden movement with the controls.

Of course, what worries Robinson here is that student pilots may make erroneous control inputs beyond what an instructor can fix to regain control of the aircraft.

What Worries Me More

January 31, 2012 note: Since writing this, a friend on the Rotorspace site has brought the topic of Mast Rocking to my attention. Apparently, some folks think that this accident may have been caused by Mast Rocking rather than an abrupt cyclic control input. I’m not convinced. Mast rocking supposedly does not cause the main rotor blades to diverge from their normal plane of rotation. How else could the tail be cut off in flight?

But what worries me more than putting stress on components is an accident report from 2006. I read this report on the NTSB Web site not long after the accident occurred. Back then, there was no known reason why an R44 helicopter with just two people on board for a long cross-country flight should fall out of the sky with its tail chopped off, but I had my suspicions. After my recent flight with the new pilot, I looked it up again. Here’s the probable cause (emphasis added):

The Canadian certificated commercial helicopter pilot was conducting a cross-country delivery flight with a non-rated passenger occupying the copilot seat. The passenger and pilot together had previously made delivery flights from the Robinson factory to Canada. Two witnesses saw the helicopter just before it impacted the ground and reported that the tail boom had separated from the fuselage. No witnesses were identified who saw the initial breakup sequence. Both main rotor blades were bent downward at significant angles, with one blade having penetrated the cabin on the right side with a downward slicing front to rear arc. The primary wreckage debris field was approximately 500 feet long on an easterly heading. The helicopter sustained damage consistent with a high-energy, fuselage level, vertical ground impact. Detailed post accident investigation of the engine, the airframe, and the control systems disclosed no evidence of any preimpact anomalies. The removable cyclic was installed on the left side copilot’s position, contrary to manufacturer’s recommendations when a non-rated passenger is seated in the left seat. The removable pedals and collective for the left side were not installed. The cyclic controls for both the pilot’s and copilot’s positions were broken from their respective mounting points. The copilot’s cyclic grip exhibited inward crushing. The Safety Board adopted a Special Investigation Report on April 2, 1996, following the investigation into R22 and R44 accidents involving loss of main rotor control and divergence of the main rotor disk, which included a finding that the cause of the loss of main rotor control in many of the accidents “most likely stems from a large, abrupt pilot control input to a helicopter that is highly responsive to cyclic control inputs.”

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
a loss of control and the divergence of the main rotor blade system from its normal rotational path for undetermined reasons.

(A full narrative is also available.)

This is pretty much what I’d imagined. The helicopter is cruising along at 110 knots in a very boring part of the California desert. For some reason, the pilot (or his passenger, who has access to a cyclic control), jerks the cyclic one way or the other. Maybe he was trying to dodge a bird. Maybe he was goofing off or pretending to be Airwolf. Who knows? The sudden input is enough to cause the blades to diverge from their normal path. One (or both) of them dip down and chop off the tail boom. The result: two dead bodies in a 500-foot long debris field.

And this is what was going on in the back of my mind when the pilot beside me made those sudden inputs.

Anyone who has flown a Robinson helicopter can tell you how responsive the cyclic control is. It wouldn’t take much effort to knock the blades out of their path. That’s why we’re taught — or should be taught — to use smooth control inputs.

Other accident reports like this one include: CHI05CA267 and MIA00FA102 (which is a “watch this” moment).

Other Concerns

Rotorcraft Flying HandbookThere are at least two other reasons to avoid abrupt cyclic movements. You can find all these in the Rotorcraft Flying Handbook, an FAA publication that’s a must-have in any helicopter pilot’s library.

Under the “Retreating Blade Stall” heading (page 11-6):

High weight, low rotor r.p.m., high density altitude, turbulence and/or steep, abrupt turns are all conducive to retreating blade stall at high forward airspeeds.

Personally, I don’t think retreating blade stall is an issue in Robinson helicopters, except, perhaps, at high density altitudes and high speeds. But in that case, you’d be exceeding Vne.

Under the “Low G Conditions and Mast Bumping” heading (page 11-10):

For cyclic control, small helicopters depend primarily on tilting the main rotor thrust vector to produce control moments about the aircraft center of gravity (CG), causing the helicopter to roll or pitch in thedesired direction. Pushing the cyclic control forward abruptly from either straight-and-level flight or after a climb can put the helicopter into a low G (weightless) flight condition. In forward flight, when a push-over is performed, the angle of attack and thrust of the rotor is reduced, causing a low G or weightless flight condition.

You can find an account of this (with a lucky pilot and passenger) in this accident report from July 22, 2010. Indeed, the problem may have occurred during the right turn the pilot initiated — did he jerk the cyclic over as my companion had done?

Another accident report that suggests mast bumping is SEA03FA148 (which took the life of a pilot I knew).

I’m Not Just Nitpicking

The point of all this is that I’m really not just nitpicking a fellow pilot with limited flight time. He performed a maneuver which I consider dangerous and I have all this information to back me up. It’s important for him — and for others who might not know any better — to avoid abrupt control inputs.

Robinson helicopters aren’t capable of safely performing aerobatic maneuvers. Don’t fly them as if they are.