Tag Archives: safety

Three Tips for Becoming a Better, Safer Pilot

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My take on some advice offered by the FAASTeam.

The Deer Valley Pilot’s Association (DVPA) held its annual membership drive at Deer Valley Airport (DVT) in Phoenix yesterday. I’d joined the group earlier this month, when I discovered that membership entitled me to a $1.10/gallon discount on 100LL fuel at my preferred FBO there, Atlantic Aviation. One top-off was enough savings to pay the cost of a year’s membership.

DVPA EventI was so appreciative that when I heard about the event and the fact that a few aircraft would be on static display, I offered to put my helicopter on display. So yesterday morning, at 8:15 AM, I parked on the ramp in front of the terminal building to give attendees just one more aircraft to look at. I even hung out for a while and let kids climb into my seat.

FAA LogoThere were other organizations on hand, with tables set up under a big shade. The FAA’s Safety Team, which sponsors the WINGS pilot proficiency program, was one of them. They had a table full of informational flyers. Because of my general interest in helicopter accidents — which, by the way, I’m starting to think isn’t exactly healthy — I picked up a flyer titled “Helicopter Training Accidents.” Later, back home, I gave it a quick read.

The pamphlet focused on two areas of training accidents: autorotation and dynamic rollover. It provided a lot of bullet points under headings like “Autorotation — Common Errors” and “Dynamic Rollover Precautions.” It was pretty basic stuff, but good to read just to refresh my memory. I wish I could link to it here for reference, but I simply can’t find it online. I’ve scanned it; you can download it here. And believe me, there’s lots of online reference material available at their Web site.

But the most useful content — especially for new pilots or pilots falling into the complacency trap that can catch you at any experience level — were the bullet points under “Cockpit Resource Management and Personal Readiness.” Three of these points jumped out at me as great topics for discussion in a blog post. Here they are.

Oh, and although I’m a helicopter pilot and use helicopter examples here, most of this applies to airplanes, too.

Know your limits and observe them.

I think that this is one of the biggest causes of accidents — although I’d expand it to read “Know your limits and the limits of your aircraft and observe them.” Many of the accidents I’ve discussed in this blog can be categorized as what I call ‘stupid pilot tricks.” In so many cases, pilots overestimate their own skills or the capabilities of their aircraft either in general or under conditions they’re not accustomed to.

So how do you discover what your limits are? The best way is by experience. If you’ve successfully performed a maneuver consistently over time, that maneuver is probably within your limits — in the conditions in which you’re have successfully performed it. But whenever conditions differ, you need to proceed carefully to test your limits. For example, perhaps you’ve landed quite a few times off-airport on dirt and gravel in light wind conditions. But now you need to land on terrain littered with big rocks. Don’t assume that it’s just as easy as any other off-airport landing. Consider the risks and proceed carefully. Leave yourself an out. Don’t commit to setting down unless you know you can do it safely and then take off again later. The same goes for making an off-airport landing in a strong crosswind or tailwind situation. Or in dusty or snowy conditions. Have you done it successfully before? Multiple times? Consistently? Then it’s probably within your limits. But if the situation is brand new to you, you can’t possibly know for sure whether it’s within your limitations. Proceed with caution!

Advanced training can also help. If you find yourself with a need to perform maneuvers that you’re not sure about, find an experienced CFI and go flying with him. Let him train you, let him give you the additional support you might need to practice it safely. Isn’t it worth a few hundred dollars to get the experience you need to safely expand your personal limits?

As for the limits of your aircraft, that’s pretty easy. Open the Pilot Operating Handbook and look them up. If you fly the same kind of aircraft often, you should have most of the limitations memorized, including a rough estimate of out of ground effect hover capabilities at various weights and density altitudes. And if you find yourself in a situation where you’re not sure if an operation is even possible for your aircraft, reach for that book and look it up to make sure. It’s required to be on the aircraft, so there’s no excuse not to consult it. I’m not ashamed to admit that I’ve done this several times. I even keep a copy of the book in my office to make sure I can handle unusual client requests before booking a flight.

Develop and use good habits (e.g., checklists).

The FAA loves checklists and I’ve been told by a few pilots that they won’t let you pass a check ride unless you use available check lists during the flight. While I agree that checklists are extremely helpful — I actually created my own for preflight, startup, and shutdown when I flew LongRangers at the Grand Canyon back in 2004 — I also feel that if you perform the same series of tasks in the same order without distraction more than 50 or 100 times, a checklist becomes a bit redundant. So if you’re expecting me to wax-poetic about checklists, I’m sorry to disappoint you.

What I will expound on, however, is the idea of developing good habits for all phases of flight. Here are a few examples from my own flying:

  • Always perform a preflight inspection in the same order.
  • When adding oil during preflight, always leave the cowl door open until the oil cap/dipstick is replaced. Do not close that cowl door unless the cap/dipstick is confirmed present and tight.
  • Just before stepping into the aircraft, always do a complete walk-around starting and ending at the pilot door. Use that walk-around to check for open cowling doors and fuel cap tightness one more time.
  • Always perform all parts of the startup procedure, from sitting in the pilot’s seat and fastening my seatbelt to loosening frictions just before bringing RPM to 100%, in the same order.
  • Always check to make sure all doors are secured before lifting up. (I can reach all doors from my seat and all their windows have fingerprints where I push on them before each flight.)
  • Always do a visual scan of the area before lifting up and then again before departing the area.

These things, when done regularly, become routine. I actually feel as if something is wrong if I neglect to perform one of these tasks. I have even gone so far to climb back out of the aircraft before starting up to check fuel caps if I can’t recall doing so.

What’s a bad habit? How about storing papers, pens, or other items in the area beneath the collective? While some aircraft have ample storage space there, many do not. Don’t place anything there that could prevent you from getting the collective down in a hurry if you need to. How about leaving dual controls in when non-rated passengers are on board? Do you really want to worry about some idiot pushing the cyclic, resting his feet on the pedals, or having his fat butt blocking the collective when you’re trying to pull pitch? Pull those controls out if you don’t want the person beside you able to mess with them. Or how about glazing over or skipping your passenger preflight briefing? Do you know how you’d feel if your passenger were trapped in the aircraft after a mishap because you neglect to tell him how to open the door?

Think about the things you do when you fly. What good (or bad) habits have you developed? Get rid of the bad ones — they’re not going to help you become a better or safer pilot. Instead, think about the things you need to do or be aware of when you fly and incorporate them into your workflow or cockpit management.

Be constructively critical of each flight.

This is my favorite of the tips, the one that made me think this was a topic to blog about.

The trouble is, too many pilots are head cases who think they can do no wrong. No matter how well or poorly they fly or complete a mission, they’re too full of themselves and confident in their own capabilities to review what they’ve done and think of how it could have gone better.

The Pick Up/Set Down Challenge

I must have written about this elsewhere, but I can’t find it so here it is.

When I flew at the Grand Canyon in 2004, I averaged 10-14 flights a day. The flying itself was rather tedious, with only two extremely well-defined routes and no room for deviation. There wasn’t any opportunity to make it more interesting — other than the challenges Mother Nature threw in our way — so I decided to focus on the part of the flight where there’s always room for improvement: those 10-14 pickups and set downs.

From nearly day 1, I concentrated on that part of the flight, working hard to make every single pick up or set down as smooth as I could make it. Then, right after each one, I’d give it a score from 1 to 10, with 10 being the kind of pick up or set down where you didn’t even feel the aircraft make or lose contact with the ground. I didn’t have many 10s — I’m a tough scorer — but after a few weeks and months, I didn’t have many below 6 either.

To this day, I do the same thing with pick ups and set downs. The result: I’m pretty sure that few fellow pilots would find much fault in most of my pick ups or set downs. The passengers think they’re great no matter how low I’d score them — but what do passengers know?

Have you ever considered doing something like this for your flying? Challenging yourself for no other reason than to improve yours own skills? If not, why not?

The reality is that anyone can improve at least one aspect of any flight or mission. Just think about everything you did and focus on what wasn’t perfect. Then think about what you could have done to make it perfect — or at least closer to perfect.

Here are some examples:

  • During preflight, did you miss any inspections you should have done because you were distracted? If so, how could you prevent future distractions? (A friend of mine will restart a preflight inspection from the beginning if anyone interrupts him while he’s doing it.)
  • Did startup go smoothly? If not, what could you have done to make it better next time? (I’ve gotten to the point where I usually know how long to prime the engine before starting based on the ambient temperature.)
  • Was your departure smooth and within height-velocity diagram recommendations (if possible)? If not, what could have improved it?
  • Were your radio calls well-timed, concise, and correct? Is there anything you could have done to make them better?
  • Did you choose the best route to your destination? If not, what route might have been better and why?
  • Was your approach to landing suitable? If too steep/shallow, fast/slow, or with a tailwind, what could you have done to make it better or safer?

I can go on and on with examples, but you get the idea. Review each flight or mission and make mental notes about how it could have been better. Then, the next time you fly, act on those mental notes as appropriate. Not only will this make you a better, safer pilot, but it could help you develop some of those good habits I discussed earlier.

The point is, no matter how much experience you have and how great a pilot you think you are, you are not perfect and no flight is perfect. There’s always room for improvement. It takes a good pilot who is genuinely interested in becoming a better pilot to recognize this and work hard to get better. And better. And better.

Only You Can Make Yourself a Better, Safer Pilot

Not only is it within your control and capabilities to make yourself a better and safer pilot, but it’s your responsibility to do so. These three tips are a good place to get started.

What do you think?

Dangerous Flying: Abrupt Control Inputs

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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.

Update, March 17, 2012: Here’s another example of an accident likely caused by an abrupt control input. This one resulted in mast bumping.

On “Aspiring” Helicopter Pilots

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Get a clue.

Earlier this week, I pulled together clips from a two-hour flight between Phoenix and Page, AZ and made it into an eight-minute video set to some solo piano music. It’s not a masterpiece of video editing — hell, that isn’t what I do. It was just a way to create some fresh marketing material for Flying M Air using what I thought was some pretty awesome video footage from my flight.

I blogged about the trip and embedded the video here.

A Tiny Bit More about the Video

I need to make a few points about this video before I start my rant:

  • Route to PageThe purpose of the flight was not to make the video. The purpose of the flight was to get from Phoenix to Page as quickly as possible. My clients paid for two hours of flight time; every minute past that was being paid for out of my pocket. I flew nearly a straight line, as shown in this Google Earth plot created from actual GPS points. (I sometimes run a geologger while I fly; I happened to have it running that day.)
  • The primary purpose of the video was as a marketing tool. I had good, smooth footage of places I often fly. The lighting for some of the flight was excellent. The footage was representative of what a client might see while flying with me. Why not turn it into a marketing video?
  • The only footage in the entire video that I considered not including were the low flight clips over the Navajo reservation, including the clip where I fly between two buttes. The reason: it is not representative of what a client might experience when flying with me. Why? Because my Part 135 certificate requires me to maintain minimum altitudes of 300 feet AGL with passengers on board during a Part 135 flight. Coincidentally, this footage also documented some of the more exciting portions of the flight — 110 knots at low level isn’t exactly dull when you’re experiencing it.
  • The overall tone of the video is peaceful and serene. I was showing off beautiful scenery that floated by beneath us. The music seemed to work with it.

I shared the video on this blog (as mentioned earlier) and linked to it in a few places, including a social networking site for helicopter pilots. I got a lot of positive feedback that made me feel good.

Enter, the “Aspiring Pilot”

On the helicopter site, a lot of pilots complemented me. A few asked questions, which I answered. And then Dan (not his real name) commented:

I’ll still look like a little jerk, but god that that flight is boring. I dare not imagine the other 112 minutes. A helicopter is made for fun, caution kills the fun !!

I was immediately taken aback. I never intended the video to be exciting. Hell, if I made it too exciting, it would have raised all kinds of red flags with my contacts at the FAA. It was just a marketing video.

And then I started thinking about what the little jerk — hey, it was his self-applied label — had just said: “caution kills the fun!!” What kind of pilot would say such a thing?

I checked out his profile and it became clear. He was an “aspiring pilot.” In other words, he wasn’t a pilot at all.

Instead, he was an immature, idiotic wannabe.

I knew the type. They think flying helicopters is cool, mostly because of what they’ve seen in the movies. (I assume not the scenes where the helicopter explodes.) They’ve never been at the controls of a helicopter, they’ve never read anything about helicopter aerodynamics or maneuvers. They don’t know the first thing about flying helicopters. Maybe they’ve never even been close enough to a helicopter to touch it — let alone sit in one.

But they’re experts!

“A helicopter is made for fun, caution kills the fun!!”

They hang around helicopter forums, trying to fit in, trying to make cool comments that’ll score points with people they see as their peers. Instead, they just spout inane bullshit:

“A helicopter is made for fun, caution kills the fun!!”

The helicopter forums are full of little jerks like this — which is why you won’t find me on the helicopter forums. I have no patience for the kind of crap put out by wannabe helicopter pilots who haven’t got a clue about flying helicopters.

“A helicopter is made for fun, caution kills the fun!!”

Attention “aspiring pilots”: a helicopter is not “made for fun.” It’s a utility aircraft that can perform maneuvers and operate in situations impossible for an airplane. It is a complex piece of machinery. It takes real skill and knowledge to fly.

A lot more skill and knowledge than you’ll get playing with your Flight Simulator.

And caution? Well, that’s what keeps you alive so you can fly again tomorrow. It’s also what keeps your passengers alive so they can tell their friends about how great it was. It keeps your helicopter in one piece so its owner doesn’t take a huge financial hit. It keeps the FAA off your back so you keep your license. That’s what caution does.

Flying helicopters is serious business. It isn’t a game. Any pilot who doesn’t take flying seriously is a pilot I don’t want to see at the controls of an aircraft.

Wanna Be a Pilot?

Stop pretending and start studying.

And shut the hell up until you know what you’re talking about.

A Lesson in High Density Altitude

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Hot and high make for bad flying weather.

Earlier this month, I gave helicopter rides at the annual Old Congress Days celebration. This is my fourth or fifth time attending the event. I don’t make much money at it — I usually price the rides too cheap for that — but it is one way of giving back to the community. The folks in Congress, AZ do their best to make it a great event for everyone and I try to do my part.

My landing zone for this event is probably the nicest helipad I’ve ever been privileged to operate from. It’s the medevac helicopter pad next door to the local fire station. Congress is about a 20-minute drive from the nearest hospital, in Wickenburg, and at least an hour from a better-equipped hospital down in Sun City. If you need emergency medical attention for a serious matter in Congress, they’ll send a helicopter to pick you up and it’ll land right beside the fire station in the middle of town.

Congress Helipad, Close UpThe helipad is a 75-foot square of concrete, marked with a big, white, reflective cross in the middle. Around that is another 20-25 feet of big, dust-free gravel. A four-foot fence surrounds the whole thing (see red box). Access is from the street side only, where a double gate can open to admit an ambulance. A concrete path leads up to it so pedestrians don’t need to walk on the gravel.

As a landing zone for an event, it’s a helicopter ride pilot’s dream come true. There’s no reason at all to worry about access to the area, since everyone has to go through a gate which my ground crew keeps secured. After the first landing, no dust is kicked up into spectators’ faces or the rotor blades. The pad is flat and level and smooth.

It would be perfect if not for one thing: I had to come and go.

And that’s always been the problem with this landing zone. I only feel safe coming and going from the east (right in this photo). The fire house building is to the north and relatively new metal building stands to the south. The event is to the west and several strands of wires hang at the usual height from telephone poles between it and the helipad. The east is the only direction where I don’t have to fly close over a building or crowd of people. Of course, to the east there are also some desert trees up to 15 feet tall and a railroad track that gets freight trains a few times a day.

I’m not saying the landing zone is impossible. It’s certainly not. But it’s the kind of place where you need to keep on your toes whenever you take off or land.

The Usual Routine

Normally, the wind is coming from the north, south, or west. That’s okay with me, unless it’s howling. I’d rather take off with a tail wind and land with a headwind than the other way around. The way I see it, if I can take off with a tailwind, I’ll have no trouble landing with a headwind.

When the wind is coming from the north, I take off to the northeast and land from the southeast — quartering headwind both ways. When the wind is coming from the south, I take off to the southeast and land from the northeast. Same quartering tailwind situation.

I always park with my tail rotor facing away from the path. I don’t want to give passengers any reason to even think about walking behind the helicopter. The single member of my ground crew loads one side of the helicopter at a time. He walks two passengers from the gate to the helicopter’s left side while a third passenger (if there is one) waits at the path. Once he’s loaded the first two and closed their doors, he walks the third person to the seat behind me. Once the doors are closed, he gives me the thumbs up signal as he walks back to the path.

When he’s clear and I’ve double-checked the doors — a good habit I’m not going to break — I pick up into a hover, pivot around to face my departure path, and take off. I then do a loop around the entire town to the left. It takes 5-6 minutes. I finish off by coming in on my chosen arrival path and landing back on the pad.

Arrival and DepartureThis photo shows my arrival and departure paths with a few points of interest.

  • The blue lines are all wires. They’re the standard height wires you find on wooden telephone poles.
  • The yellow line is my departure path. I need to fly parallel to the railroad tracks until I have enough altitude to see if a train is coming. (I can’t make this stuff up.) If a train is coming, I need enough altitude to fly over it. I also need enough altitude to get across the wires on route 89 when I make my left turn.
  • The magenta line is my arrival path. I need to clear the wires on route 71 on my final descent. I’ve already confirmed no train is coming, so I know I can come in nice and low over the tracks.
  • Both paths avoid the desert trees growing between the helipad and the tracks.

One of the challenges to this path is the six-foot fence around the metal building south of the helipad. You can see it as blue lines in the first satellite photo. It’s only a few feet from the helipad fence and I cross over the corner of it while I’m climbing out. Going beyond the corner would bring me tool close for comfort to those train tracks with no way of knowing if a train was just beyond the building and trees.

Sounds challenging and it is. But I’ve been doing this gig for a bunch of years and I just deal with it. After all, I’ve worked with much worse conditions at other gigs. Despite the confined space aspects, this is still pretty darn good.

Add Heat

This gig is in October every year and Congress sits at right about 3,000 feet elevation. The temperature is normally in the high 70s or low 80s. Warm, but not to the point where it becomes an issue.

But not this year. During the October 2, 2010 event, my outside air temperature (OAT) gauge read anywhere from 90°F to 102°F. It was freaking hot. So hot I took my door off before I started flying and flew with a bandana full of ice cubes around my neck.

Doing the Math and Why It Matters

Density Altitude ChartLet’s do some pilot math here through the use of a density altitude chart. At 3,000 feet elevation with an outside air temperature of 35°C (roughly 95°F), the density altitude is about 6,000 feet. That means my aircraft would perform as if I were taking off and landing at a helipad at 6,000 feet elevation rather than 3,000 feet.

If you’re not a pilot, you probably don’t understand why this matters. The simple explanation is that aircraft performance drops off as altitude rises. This has to do with the density of the air. At high density altitudes, the air is thinner and aircraft simply don’t perform as well as they do at sea level.

I knew this was going to be a problem when we took off at Wickenburg at 9 AM that morning. With full fuel tanks, two people on board, and about 50 pounds of landing zone equipment, I had to pull 22 inches of manifold pressure to get off the ground. On a cooler day, 20 or 21 inches would have done it. I immediately started wondering how things would be with two or three adult passengers on board.

I found out at about 10:20 AM, when the parade ended and the passengers started lining up. The first flight was just one passenger, a friend. By that time, the temperature was already in the 90s and the helicopter felt slightly sluggish. The second flight had two passengers and that was enough. On departure, I passed through effective translational lift (ETL) right around the time I reached that six-foot fence. The resulting dip before the post-ETL power boost kicked in brought me within 5 feet of the top of that fence. I was not a happy camper.

On the next flight, before taking off, I hovered to the north side of the pad to give myself a running start at that damn fence. It made a difference, but not a big one. I could count the barbs on the top strand of wire every time we passed over it.

Using High DA Experience

I have to admit here that I was using all my high density altitude experience for every departure. In the grand scheme of things, 6,000 feet DA isn’t a lot for me. I’ve successfully landed and taken off at airports with 9,000 or 10,000 feet density altitude. The density altitude was over 10,000 feet a few years back when I departed Bryce Canyon Airport in my helicopter with three people on board.

When I flew at the Grand Canyon in 2004, I flew Long Rangers from a base at 6,300 feet with temperatures as high as 95°F. If you pull too much pitch on takeoff in a turbine helicopter, you’ll over-torque the engine and possibly destroy the transmission. If you didn’t learn the tricks for getting off the ground with a full load of German tourists, you’d be putting a helicopter in the shop with a $100,000 repair bill.

In the R44, you can pull as much pitch as you want without bothering the transmission, but there will come a point when there simply isn’t enough power to spin the blades at full RPM. When the low rotor RPM horn goes off, you want enough wiggle room beneath you to lower the collective to regain lost RPM. That isn’t going to be possible with a fence just a few feet away. So I wasn’t about to pull more pitch than the helicopter would give me. I trusted my ears to tell me when I was pushing my luck with the collective — I can always hear the rotor RPM droop before the horn goes off.

Why Full Fuel?

Now you might be wondering why I had full fuel tanks. Simple: there was no fuel at my landing zone. I’d planned to fly until I had enough for my 10-minute flight back to Wickenburg and 20-minute required fuel reserve. Since I’d be spending a lot of time on the ground, spinning between flights, I needed to start with as much fuel as I could if I wanted to maximize fly time — and profits.

The problem with this plan was that I simply did not have the performance I wanted to take three adult passengers at a time. And there aren’t many kids in Congress. As a result, I did almost every single flight with just two passengers on board, netting just a few dollars on every flight — and sweating my brains out while I did it.

Just Can’t Do It

I was down to 2/3 tanks when my ground crew guy tried to put three adults on board. The two women weren’t big, but the man was 245 pounds. Our total weight was right about at our limit for an out of ground effect (OGE) hover. I pulled pitch slowly to bring it into a hover. I was at 23 inches of manifold pressure hovering over the pad. I’d need at least two inches more to clear the fence on what was essentially a maximum performance takeoff from a confined space. And, given the conditions, I just didn’t think I had the power I needed.

All I could think of was hitting that damn fence with three passengers on board.

I set it back down and told them that either one of them needed to get off or they all needed to come back later, when I’d burned off more fuel and was lighter.

The OGE Chart

As my ground crew guy offloaded them, I consulted the pilot operating handbook (POH) to see exactly what the OGE chart said. According to the chart, it was possible to hover out of ground effect in the conditions of flight — but just barely.

You might be wondering why I consulted the OGE hover chart instead of the IGE (in ground effect) chart. After all, ground effect is in play for about one rotor diameter — in my case, about 28 feet — from the ground. The fence I feared was only 6 feet tall.

R44 OGE ChartI guess the easiest way to explain it is that the OGE hover chart is the best indicator of the most power I’ll have in the worst possible condition. It takes more power to hover than to fly and it takes more power to hover OGE than IGE. So if you want to know what the maximum performance is in a worst case scenario situation, consult the OGE chart.

(I should mention here that the OGE chart for the Robinson R44 Raven II is the reason I bought a Raven II instead of a Raven I. The Raven I OGE chart (which can be found in this post, also dealing with high DA) told me that I simply wouldn’t have the performance I needed to operate in Arizona’s relatively high elevations in Arizona’s hot weather. It was a no brainer and worth the extra $40K to have a better performing aircraft. I don’t regret my decision one bit.)

To read this chart, you follow the weight line (roughly 2,400 to 2,450 pounds; I always use the highest estimate) up to where it intersects with the temperature line (35°C) and then follow it across to the pressure altitude. In this case, it says I can hover out of ground effect at 3,000 feet, which is exactly where I was.

But what if I didn’t have the skill? What if the helicopter wasn’t properly tuned? The chart is created by test pilots with thousands of hours at the controls of all kinds of helicopters. I have about 2,500 hours, of flight time with less than half of that in my R44. Just because the chart said it was [barely] possible doesn’t mean I could pull it off. I wanted more wiggle room.

And That’s What Experience Teaches Us

Experience doesn’t only teach us how to fly better and to make the helicopter perform in difficult situations. It also teaches us to recognize when performing a maneuver or operation might not be safe.

It gives us the courage to say no, this isn’t something I want to do.

I remember one hot day at the Grand Canyon back in 2004. I was flying Copter 9 (I think), which had a reputation for being a “dog” — an under performer. The company tower controller called me on the radio to ask if I could take 4,150 pounds. The helicopter’s max gross weight was 4,200 pounds and it had been performing like its usual crappy self all day with every load around 4,000 pounds. I’d even “beeped” it a few times on takeoff — pulling a tiny bit more than 100% torque for a second or two. I didn’t think 4,150 was a good idea. I said no.

Sure, I could have tried taking a heavier load. And I could have hit the JetA fuel tank at the end of our departure area or overtorqued the aircraft. Or I could have got off fine. Was it worth trying to find out how it would all end?

Of course not. Safety first.

There are old pilots and bold pilots, but there are no old, bold pilots.

My Three Passengers

The same three passengers tried to board again 15 minutes later, after I’d burned off only 24 pounds of fuel. I told my ground crew guy I needed at least an hour. They hung around for a while, watching me come and go. All my flights had only two passengers on board — except one flight, where I took a mom and two small kids.

They disappeared while I was out flying. Later, my ground crew guy told me he’d given them their money back. I was glad.

Maybe next year, the temperature at Congress will be more seasonal. And maybe next year, we’ll bring the last 10 gallons of fuel in cans.

Low Rotor RPM Warning System, Illustrated

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A video to go with an earlier blog post.

I’ve written at least twice in this blog about the low rotor RPM warning system on Robinson helicopter:

I thought it might be good to illustrate what it looks and sounds like on video. You can find the video at the bottom of this post.

Before you watch the video, please read this explanation. The video is not narrated; I wanted the helicopter sound to be heard. If you don’t read this, you won’t know what’s going on or why.

  1. At first the helicopter is at cool-down RPM (around 65%). I’d just come in from a flight and was getting ready to shut down when I decided to use my Flip camera to make the video.
  2. I wind up the RPM by twisting the throttle. Watch the tachometer in the upper right corner. Needles are matched for engine (E) and rotor (R) RPM.
  3. When RPM gets to about 80%, the R44’s electronic governor takes over and brings it up to 100-102% engine RPM (the green arc).
  4. I simulate a low rotor RPM situation to test the system. (The system is required to function for flight so I test before every flight.) This requires me to raise the collective about an inch and then slowly roll off the throttle to reduce RPM. You can hear the engine pitch change and see the needles start to droop.
  5. At 97% RPM, the warning system engages with an audible horn and a light. A pilot who misses this would have to be blind and deaf (and thus, would not be good as a pilot).
  6. In the test, I push the collective down to shut the horn off and let the governor roll the throttle back up. If the horn came on in flight, you’d use the low rotor RPM recovery procedure, as discussed in “Reacting to Low Rotor RPM,” to regain RPM before it dropped to the point where it was not recoverable and became catastrophic.

Here’s the video:

The system looks and works slightly differently on different helicopter models. But the basic operation and test is the same.