Log

World's Hardest Aircraft

It may verge on brainless to fly, but the launching? Not on your life!

Yeah, I know, flying a paramotor is easy, right brake to turn right, etc. But launching? I don't care how many times you're successful, it's still hard. Even for those who nearly always make them: they barely make it.

Little things can trip you up, too. I try different gear all the time and, every now and then will get stumped. It's a challenge that I kind of enjoy, though, to sort out what technique works best even if it takes 6 tries to get airborne. I keep trying. Admittedly, there is a time to quit, but I have yet to meet a combination that I can't sort out. One wing that took me probably 7 tries (and nearly cost a shoe) was the "Plasma" from 8 years ago. Not that it was necessarily hard to launch but clearly I wasn't breaking the code. Sure enough, after figuring out its particular needs I had no problem and was launching it reliably on the first try.

Recently I had a launch that reminded me anew just how difficult variable-wind can be and, generally speaking, why.

Feet

It comes down to this. While hefting a pack weighing half our body weight, we can't run very fast. Obviously the motor's push helps but try this: put the motor on, run as fast as you can, then throttle up to full power. Yeah, not so good; if the wing isn't lifting, expect to face plant.

There are so many variables to a successful launch but even a slight tailwind can torpedo the effort, mostly due to a limitation on airspeed and our ability to run. My next XC column will be "Anatomy of a High Speed Launch" or something to that effect. Intentionally doing such a launch is taunting the crash demons but sometimes nature doesn't allow us intent.

The book calls it "leg drag" since most of us can't run over 4 to 6 mph while carrying our gear until the wing starts lifting. But without airspeed the wing doesn't lift. AIRspeed. It doesn't matter how fast you're running, if there's not sufficient AIRspeed over that wing, it's not lifting--lifting enough to matter, anyway. And yes, of course a bigger wing helps!

Stall

The normal technique is to get the wing overhead, accelerate, add brake to get some lift from the wing to take the motor's weight off, accelerate to get more lift to make you lighter in the feet to allow faster running and more airspeed, etc. Generally speaking it works pretty well. Anybody who has launched from 10,000+ density altitude in no wind probably already knows about this. Launching a tiny wing is the same thing.

Close Call

I'm motivated by a recent jaunt where Tim and I launched right from our front yard. Light and variable--emphasis on variable--oozed from the west/northwest down our north/south runway. Sometimes it was south, sometimes it was north, most of the time it was non-existent.

I'm flying a wing (Doberman 18) that I've become reasonably familiar with and have a decent feel for. It's quite reliable in no wind.

After waiting for a tailwind to subside I went for it. The wing came up sluggishly so I stayed on the A's while accelerating. This time it came overhead I was running fast and had to pull right brake to turn and run down the runway. Still running very quickly I pulled both brakes to get some lift so I could run faster. That's when I felt the right brake go soft and realized that the right side must be stalling so I immediately let up the brakes to let it get fully flying. At that running speed it should have been but obviously wasn't and I was now close to full power.

Soon after letting off the brakes I was able to run faster yet, come in with some brakes and now the wing was lifting. That started the positive feedback look of success: more lift meant less leg drag which allowed more speed which added more lift which... you get the idea. The launched worked but it was DAMN close!

Wheels

Don't let anyone diss wheels, most of us will retire from paramotor on them and that's not a bad thing. Plus, I contend that, for experienced pilots they're much safer in these conditions.

Wheels have their own challenges but, for the most part, they don't care anywhere near as much about a 1 mph tailwind. For an experienced pilot who knows how to reduce rollover risk, they make handling this condition dramatically easier and, I suspect, less risky.

Wing Choice, Conditions & Take Home

Yes, of course wing choice matters but, regardless of what you're flying, it needs airspeed so this can happen to anyone, on any wing, at any wing loading. The Doberman happens to be pretty fast and I'm on a small size which aggravates this.

It doesn't have to be variable wind, either. You might think "I don't fly late morning" but I've had it happen where the wind, up at wing height of 12-15 feet AGL, is noticeably different.

One of the most important takeaways is to abort if it starts getting hairy. That's tough because, at some speed of running, aborting without falling can be difficult, too. It's still better than higher speed buffoonery.  No, the best bet is to avoid the condition whenever possible or wheel up. Otherwise, if you accept the risk, enjoy the challenge!

Running, flying, and landing. It was a great little romp.

On a late morning launch, Tim and I set up into the prevailing light westerly wind but it was frequently tailwind if we went north down the runway. He's pointed slightly north of west here  and will have to turn north, as I did, to run down the runway.

The fact that these launches worked belies a couple realities: 1) how remarkably important instruction is 2) how difficult launching this craft can be in these conditions.


2015 Jeff Goin   Remember: If there's air there, it should be flown in!