Ask an Engineer: helicopter/airplane pilot seat location

At my current base, I offered to write a monthly “Ask an Engineer” column, where base clinicians write in with questions on helicopter design and engineering, and I answer them. This is my first column:

Why do helicopter pilots sit on the right, while airplane pilots sit on the left?

The short answer is because that’s what pilots are already used to, and any new aircraft are designed to fit current pilot preferences. That begs the question, though: how did each tradition get started, and more importantly, why are they different between helicopters and airplanes? There’s no generally accepted single answer in either case, but a combination of the following is most likely:

Modern airplane design conventions first appeared in the 1920’s and 30’s. During that time, most airplanes were powered by large nose-mounted single engines and propellers. Most engines at the time rotated such that their torque made it difficult to turn the airplane to the right on the ground, which meant that pilots preferred to make ground taxi turns to the left. Also, most airplanes during this time had tailwheels, and sat (and taxied) nose-high. Pilots therefore preferred (so airplane manufacturers designed) airplanes in which pilots sat on the left, so they could see best in the direction they were most likely to turn on the ground.

There were aerial navigation reasons for pilots to prefer sitting on the left side, as well. Navigation at that time was mostly done by flying between visual ground checkpoints (bonfires, in the early days!), and it was convention for pilots to fly on the right side of those checkpoints, so as to stay clear of pilots using the same ones going the opposite direction. Most airport traffic patterns utilized left turns, as well. Flying on the left side, then, give the airplane pilot the best field of view to look for other air traffic near checkpoints and airports.

Helicopters became commercially viable later, in the 1940’s, and that’s when their design conventions began to solidify. The first mass-produced helicopter was the Sikorksy R4. It had two seats, and was originally designed to be flown from the left seat, perhaps to match already-established airplane design conventions. The test pilots for the aircraft were its first instructors, and mostly flew it from the left seat, and therefore their trainees mostly all learned to fly it from the right. The test/instructor pilots trained many more pilots than they themselves numbered, so the preference among early helicopter pilots (around which, again, the manufacturers designed) was to sit on the right.

Another potential reason for the start of the tradition was the location of the helicopter’s controls. In order to save weight and reduce complexity, early two-pilot helicopters like the R4 had only one collective control, in between the pilots. Most pilots are right handed, and preferred the control that required more finesse (so the cyclic control) to be manipulated by their dominant hand, which meant that they preferred to sit on the right.

The previous are the most likely reasons why pilots sit where they do now, but there are some interesting modern exceptions to this convention. The most common of these is the Airbus H130 (previously Eurocopter EC130), in which the pilot sits on the left. The reason for this is that, though it’s widely used in helicopter EMS these days, the H130 was originally designed as a tour helicopter. Eurocopter extensively solicited tour operator input during the design process, and one of the things the operators told them was that in helicopters then used for tours (predominantly the AS350 AStar and B206 JetRanger/LongRanger), some front-seat passengers, attempting to enter the aircraft, would grab anything that looked like it might be useful in pulling themselves into the helicopter, including the collective! Grabbing onto it while getting inside raised the collective, causing some inadvertent (near-) takeoffs, and the operators wanted to eliminate this risk. Eurocopter felt the best solution to this problem was to move the pilot seat to the left side of the aircraft, where the collective would be near the pilot door, as opposed to between the pilot and front seat passenger. This design change worked well for tour operators, and pilots transitioning between left- and right-seat helicopters have not found it difficult to do so, so we may see even more left-seat piloted helicopters in the future.

Bad Timing

It seems my inadvertent ruining of my winter gloves (note to self; do not put gloves in the dryer without checking their label first) came at a particularly bad time: the very cold winter weather the US has been having has made new winter glove demand far outstrip supply. There are none at brick-and-mortar stores, and even the gloves I ordered online on January 23rd are out of stock, and have been delayed until 3/31/14. I am one small data point in a vast economic object lesson!

To prospective auto buyers

If you’re in the market for a car or truck, and you’re leaning toward one that’s bigger than your person/cargo carrying needs, please carefully consider your reason for doing so. For many people, the fundamental reason is fear: either of death/injury, or powerlessness.

If the former, note that although you may be a bit safer in an accident, the chances of having an accident in the first place are extremely low (so there’s no need to make it such a high priority in the buying decision), and that modern safety equipment has mostly negated the difference in safety between larger and smaller vehicles. Note also that whatever safety advantage you might have in an accident directly translates to equivalent increased risk to passengers in every other vehicle.

If the latter, note that there are far better (cheaper, more rational) ways to confront this fear.

Regardless of the reason, remember that your actions have consequences. In this case, the consequence of millions of people compensating for their fears with SUVs is that the environment is being destroyed. And though you may not live to see that consequence, your children, or the children of your friends or relatives, will.

So please think before you buy.

Rest of the world, here I come!

I just confirmed my hotel, flight, and tour reservations for my first trip to outside the North American continent. I’ve been to Toronto, Cozumel, and just across the Arizona border to Mexico, but I’ve always felt terribly ignorant of the world outside the US. And now, I’m finally taking the first step in doing something about it. I plan to go further afield (Germany, France, Australia, then beyond), but for now, on June 19-25, London and the United Kingdom await!

Being “normal” never felt so awesome

Like most thirty-somethings, my weight has been gradually creeping up over the last five years or so. Last December, it hit 188, which was ten pounds over the BMI normal/overweight cutoff for my height.

They say that most drug addicts can’t quit until they make the decision to do so, and that they usually don’t make that decision until they hit some personal low that’s a trigger for them. It’s different for every addict: some decide to go clean when they first wind up in the ED, or when they’re first arrested, or first imprisoned. For some, of course, it sadly never happens.

I think it works the same way for people who decide to lose weight; at least it did for me. When I hit 10 lb over the limit, I finally decided to get serious. I cut way back on (but didn’t eliminate) carbs, stopped eating sweets, and started weighing myself every morning with a scale that could provide accurate, precise (to +/- 0.2 lb) measurements. And amazingly (at least to me), the weight almost instantly started coming off. It didn’t, of course, happen overnight, and there fluctuations due to water or eating more than I needed, but the general trend was noticeably (0.2-0.4 lb per day) downward.

I hit a plateau in the low 170’s near the end of February, but I kept doing what I had been doing, knowing that I was on the right track. My goal was 10 pounds below the BMI cutoff.

This morning, I stepped on the scale.

It read 168.0.

I had done it! And I look better, have more energy, and my clothes fit better.

The best part of all this, though, isn’t the preceding. The best part is, after three months of eating differently, my habits have changed: I’ve finally shed (so to speak) my junk-food vegetarian ways. I eat more veggies and protein, and less garbage. And now that the habit is ingrained, I should be able to continue it in the future, continuing a thinner, healthier me.

I feel as if I’ve been walking around all day with AC/DC’s “Back in Black” as my own personal soundtrack. :)

Rockville, MD Apartment Hunt

My sweetie and I recently went looking for an apartment together. These were our criteria:

  • Close to Twinbrook Metro station (to minimize her commute)
  • Accepts cats (I have one)
  • Available parking for two cars
  • Two bathrooms
  • Gym/pool (not required, but nice to have)

To that end, I made a table with all the apartments within an approximately 30 minute walking distance to Twinbrook. My sweetie tells me that the table would be of general interest; you can therefore find it here. If you are looking for an apartment in the Rockville area, be sure to also check out Montgomery County’s housing site, here, as well as a map of complexes in the area, here. (You can get Montgomery County’s version of the map by clicking the “Printable Map” link at the bottom of each apartment’s individual result on their housing search site.)

Neither the map nor the site had up-to-the-second information, but we found them both to be a great start. Happy hunting!