Hard landing

Lessons from the lighter side

© 2015 RC Scale Airplanes. All rights reserved.

Let me begin with a mea culpa: I admit, I only started watching the clip below for a bit of a laugh. 

Don’t get me wrong – I have profound respect for the skill, patience and resilience of the people who build and fly model planes. Especially the resilience: Hundreds of hours on the workbench; tens of seconds on the wind…

But if you do have a chuckle (I did), just remind yourself that this video wasn’t posted for purely documentary purposes. (I did that, too.) 

The clip has garnered over 3 million views since it first went up in 2015, so it’s not the usual thing I pick out for sharing. However I doubt many of those millions lie outside the Venn Diagram for “people who fly model planes” and “people who laugh at others’ misfortunes”.

And there’s definitely another level of value here for real world aviators. 

The ‘Oh Shirt!’ moment

The very first incident is the nightmare scenario (in small planes, anyway) of an engine failure after takeoff – at the precise moment the pilot was occupied with raising the gear too. It’s not beautifully handled, but it is successfully handled and the passengers could well have walked away.

I hasten to add that it’s a superb model. 

© 2015 RC Scale Airplanes. All rights reserved.

The way the event plays out is (I suspect, anyway) a pretty accurate analogue for how it would happen in real life. Look for the initial “Oh shirt!” moment while the pilot gathers their thoughts, then quick actions to keep the plane flying, keep flying the plane, and get it down in one piece. A great lesson and all without anyone getting hurt.

The next EFATO isn’t quite as pretty, but it shows the other benefit of small scale – relative strength.

And what follows is an instructive collection of text-book aircraft accidents, covering the usual mixed bag of handling errors, loss of directional control, airframe failures and more, that pepper every National Safety Board’s annual report. There’s even a wire strike (almost certainly fatal) and an extraordinary flutter encounter (from 05:38) that would strike fear into any pilot’s heart. 

© 2015 RC Scale Airplanes. All rights reserved.

It’s all a valuable warning to stay vigilant whenever you’re around aircraft. Delta Foxtrot Uniform. 

A recipe for disaster

More revealing, though, is the huge proportion of accidents that occur in the landing phase… A 2:1 ratio by my count. 

While the importance of speed and directional control on landing is well known, and getting too slow will start veins popping in any instructor’s neck, the importance of not being too fast is often overlooked. This clip reinforces (time and again) the value of not being in a hurry to get on the ground.

© 2015 RC Scale Airplanes. All rights reserved.

Coming in too fast, then trying to force a still-flying airplane to behave like a ground vehicle is a recipe for disaster. The impact (pun intended) is emphasised by these small scale demonstrations. But that’s not the only way to mess up a landing, and hardly the only lesson to be had.

At 2:00 a Corsair pilot demonstrates some superb decision-making by abandoning his botched approach and living to fly another day. The aircraft doesn’t appear again, so we have to assume the next landing was unremarkable for all the right reasons. The F-86 that follows underscores the point perfectly, as pilot-induced oscillations bunny-hop down the runway to their inevitable conclusion.    

At 3:00 a Piper cub loses its wheel after contacting the runway. Stand-by for a trail of yellow confetti -– then be delightfully disappointed as the pilot handles his in-flight emergency with well-deserved satisfaction. 

Want to see why you should never try to force a final turn that is late, rushed and badly set up? The inevitable stall/spin disaster is at 03:55. In real life this wouldn’t be a mildly entertaining YouTube moment either. It would be the nightly news.

The last laugh

Watch out, too, for the P-40 that skids and flick rolls on short final at 06:23. With apologies to the builder of this beautiful aircraft, thank goodness this was only a model. Still, it’s not a mistake you’d want to repeat at any scale.

© 2015 RC Scale Airplanes. All rights reserved.

And that’s the lesson you can get from all these crashes if you choose to. Just take a moment to remember the very real forces that act on every aircraft, regardless of size. 

So, once again, I don’t want to disparage the pilots of these model aircraft. I want to thank them for the lessons they’ve shared through the loss of their not-inconsiderable artworks… It’s obviously a lot easier to monitor an aircraft’s speed, attitude and aim point from inside than from some distance away.

On the other hand, none of these aircraft were landed with their gear up. So maybe the modellers have the last laugh after all. 

Anyway – watch and learn. You won’t live long enough to make all these mistakes yourself. You’ll find the video here.

(Warning: Here comes the aerodynamics bit…)

In theory, it doesn’t matter whether you’re flying a 20kg model or a 200 tonne airliner – a 20 knot wind is a 20 know wind is a 20 knot wind. It doesn’t care what size your aircraft is. Then again, it absolutely matters how much your aircraft weighs. As every glider pilot knows, weight is the key to penetration, which basically equates to not letting the air push you around.

Light Sport accidents

Thanks to inertia, a 20 knot wind can’t push a massive aircraft around as easily as a light one, and a heavier craft’s extra momentum will carry it through gusts from in front, below and the sides with less disturbance. That’s partly why maximum control deflection speed (Va) is less for an aircraft that’s lightly loaded than for the same aircraft at max weight. 

There’s also the wind an aircraft ‘makes’ by moving through the air. Again, 20 knots (or whatever combination of forward speed and actual wind) is 20 knots. 

But if a model’s stalling speed is, say, 5 knots (and I’m working on the basis that a landing is a stall executed with the wheels a millimetre above the ground) then approaching at 10 knots is going to have some alarming side effects – especially compared to a Boeing 777 landing 5 knots above its correct speed. One is double, the other is negligible. It explains why models seem so skittish in the air. 

In this excellent video on Light Sport Airplane accident rates, avweb.com’s Paul Bertorelli points out that almost half of LSA accidents involve a nearby runway. There’s that 2:1 ratio again. And the types of accidents he lists will be equally familiar now you’ve watched the RCScaleAircraft video. “Losing it on the runway in a crosswind, hard landings, overshoots, undershoots, you name it…”

He points out that experience seems to have no effect on the numbers – and asks whether lighter wing loadings and sensitive controls are more dangerous than we thought. After studying those scale accidents, it makes a lot of sense. 

16 thoughts on “Hard landing

    1. That’s the beginning of the end, isn’t i? Although, maybe they should make the controllers with bigger sticks. I can’t even control Gran Turismo with those little thumb sticks.

  1. I think learning from our mistakes is a better way to learn then just being told not to do something. It gives you a painful reason to ‘never do that again’!

  2. 09.35 BF 109 coming in to land. A LOT of novice 109 pilots did that for real, some paying the ultimate price! My late ex father In Law was a keen aero-modeller, spending an extraordinary amount of time building and perfecting, only to often have his dreams fall the ground, literally! They tend to be a philosophical bunch as a rule, but then I guess they have to be!

    I’m just glad nobody thought to film my first attempt to land a T21! But for my Instructor’s reactions/desire to carry on living, my overshoot would have ended in a tangle of wood, wire and trees!

    1. Yes, I thought of that when I watched the Me.109 landing. I suspect more ink has been spent on trying to describe the art of landing than any other phase of flight. If there IS a key, I don’t know what it is. But as Andrew pointed out in his comment, a lot of it is decided about a mile out, with a stabilised approach. Technically it’s illegal to try and land an airliner without one.

      1. Indeed! It seems model aircraft have the tendency to be skittish in the handling dept by nature. I’d guess that probably a lot of it is due to the fact that the controls in the pilot’s hands are different, remote and of course give you no positive feedback or that innate “feel” that you get from the cockpit itself. Yet model pilots often put me in mind of those very early intrepid aviators though. So much trial and error, heartache and disaster, for what sometimes seems like a rather small reward, but they always feel that it is worth it and if it wasn’t for those people, would we have aviation at all?! I can’t help but admire them for their eccentric tenacity sometimes, but….it is very hard not to find some of the footage amusing nonetheless! Sort of a guilty pleasure!

      2. Aha! Guilty pleasure indeed. Your list of reasons why models are so hard to fly seems very comprehensive – and probably cumulative. The link to early aviators is intriguing… From my experience with model pilots, they’re actually builders, and flying the thing is just an inevitable next step, or maybe a test of the build.
        For a long time I thought my father (an engineer) was into model planes. Then he built a lot of model trains and when I asked him about it he said what he really liked was the craft required for miniaturisation.
        Regardless, making stuff is a vanishing pastime that needs to be valued more.

      3. Also very true. My late ex-Father in Law was an Automotive Engineer. Takes all sorts to make a world I guess but yes, I agree that making stuff is not something people seem to do much of these days, which is indeed a great shame. When I think of all the Go-Karts my Brother and I built during our summer holidays back in our far off schooldays, or cannibalising 2 or 3 scrap pushbikes to make our own dirt-tracker before testing it to destruction! All great fun too!

  3. Yes! We also tried to make a primitive sort of Hang Glider once, out of a Garden trellis and some plastic tarpaulin. A couple of trial jumps off the shed roof however revealed the inherent design weakness as it folded up mid-leap and deposited the 12 year old yours truly in an unceremonious heap on Mum’s prized Sunflowers. She was not overly amused! My Brother’s attempt later that same summer at bungee jumping, aged 10, out of his bedroom window ended remarkably similarly! Regrettably, he had tied about three elasticated belts together to serve as a Bungee cord, one end of which was around his waist, the other end was tied to the curtain pole n his bedroom. I will leave you to visualise the result of his valiant attempt!!!

      1. Ha Ha! Perhaps there is something of the Birdman in me! I took up Gliding two years later! Safer, I’d say!

Leave a comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s