People make jokes about helis:
1) Helicopters don't really fly. They're so ugly the ground repels them.
2) The helicopter's main blades are just a big fan keeping the pilot cool. If you don't believe that, just turn it off and watch the pilot sweat.
Safer than planes? Well, they can autorotate if the engine quits -- floating down on a pinwheel, essentially -- using the energy of the fall to spin the blades fast, and then using that energy to slow the descent just before it lands. Planes must keep a significant forward momentum (glide) to land if the engine goes out.
Greek ἕλιξ (hélix, "spiral") + πτερόν (pterón, "wing")
pteron emerges from the Indo-European root "-pet" "to rush, to fly," as seen in Latin petere, "to go toward, seek"
The IE root emerges in suffixed form, pet-rā-, "feather" in Old English fether, "feather"; from Germanic fethrō, feather
Helis are as beautiful as airplanes, but beautiful in a different way. It's the difference between a dragonfly and a bird. The technology in helis is absolutely profound, given their axes, each with various torques wanting to turn it into a mechanical squirrel. These days they can essentially fly themselves: an EC135, frequently used for life-flight organizations, has auto take-off and landing capabilities, as do other helicopters.
Two friends fly these things: there's Shawn, who flew Blackhawks and now flies an EC135 for a medical service.
And there's Don, who also flew Blackhawks and now Chinooks for the military. What lucky blokes to have such toys to play with and be paid for doing so!
Great Slow-Mo with the Blades!
In the '70s I flew in what was then called a "Hughes" 500D -- also 369D -- (a "Loach" or "little bird"); it was one hot little sports car, flown by Vietnam Vet Andy Anderson. You will probably recall this type of heli from the TV show Magnum P.I. That was a 500D: [Link].
Among other antics, we took a high-speed trip across a corn field with runners inches above the stalks, then climbed for a return-to-target turn -- that moment at the top, sideways, with the headphone cables floating in the zero G. Beautiful. Tail turns, nose points down, a long dive, then levels again at speed, across the corn.... Now these little birds are called "McDonnell Douglas" (MD) 500Es, sporting a more streamlined nose. There's a NOTAR version ("no tail rotor," with, instead, a big, barrel of a tail through which forced air travels and controls the yaw -- turns the tail left or right. The NOTAR tail, really, ruins the look of the thing. No picture of that here.
Like the MD 500s, the Chinook was also used in Vietnam and is still used today. These are remarkable in their size and lift -- apparently the only helicopter that can lift not only its own weight (which means it flies), but can also lift another Chinook while flying -- twice its weight. It's a hefty bird with two sets of rotors intermeshing. At a military function, I was allowed to fly in one over the Davenport, Iowa, area sitting between the pilots on the little jump seat.
It was brilliant to see the new glass cockpit and the nav systems. You don't realize just how big this helicopter is while sitting up front: turn around and look through the rest of the house behind you and the immense back door that can open in flight for unloading. Reminds me of a song: "Our house, in the middle of the...sky. Our house --."
I mentioned above that the torques and axes can make a helicopter a mechanical squirrel. Well, there is a squirrel among these helis, the AS350 -- Aerospatiale Ecureuil (French for "squirrel") (nowdays called a "H125"). These are used for anything from mountain rescue and sling loads for construction, to heli-skiing and sight seeing. What a beauty. It's nickname, A-Star, is fitting: it is a star.
It's the versatility that makes a helicopter an amazing aircraft. It's ability to hover over an object -- astounding, not least with a heavy sling load. And it all hangs on a big fan made of incredible composite blades. The UH-60, Blackhawk, has blades with a strip of titanium on their leading edges. The Huey has a brass leading edge. The rest of the blades are a mixture of air and honeycombed aluminum covered by a metal skin. Light, strong, flexible, and shaped like a wing -- it is your wing.
Shawn says this about flying EMS instead of military:
I...miss the wider margins of flight I could do in the military. Flying just above the trees and ground was fun and exciting. We could bank the aircraft more aggressively. Flying EMS is much more tamed. We are limited to 30 degree bank angles and flight profiles that are much more limited compared to the military.
And then...there's this pilot who doesn't have grandma in the back [Link]. On the other hand, it just may be that one cool grandma is flying this bird.
The most remarkable thing about helis, though, is just how many lives have been saved by them. So many different models are used today for rescues during floods, fires, medivac during wartime ("Dustoff," which means Dedicated Unhesitating Service To Our Fighting Forces) and rescues in mountain areas, including ski resorts as well as wilderness and high-cliffs -- countless operations since the creation of a stable heli platform. And then there's rescue at sea: the Coast Guard. This is not to mention the invaluable (but dangerous) service in fighting fires. Helis are astounding birds. Since I was a lad, I always thought of their kinship with the dragonfly, which amazes with its abilities to hover and then dart away in a flicker.
Among the trophies, the one bird that must have rescued more people than any other heli type is the Huey. Many are still flying. Others have been consigned atop a post at a military...post.
The development of that stable platform was largely the doing of Igor Sikorsky, who liked to fly in his suit and hat -- just as any good business person would do.
What he started: here's a UH-60 Blackhawk (yes, a Sikorsky) performing a rescue -- planting one wheel on the mountain (one of Colorado's Maroon Bells), holding the hover, while a person is loaded in [Link].
As a tribute to some of these friends and pilots, I put some UH-60s in bottles.
One last story from a former chair of my department, Frank. He flew during the Korean War era; afterwards, he flew DC-6s for an airline, but then decided to do a Ph.D. while flying for the military reserves. During the '60s -- with their anti-war (Vietnam) protests on university campuses -- Frank taught in Iowa; there he flew a Huey UH-1 out of the local airport as a reservist.
And? One day rumors circulated that the university students were planning a massive anti-war protest for that afternoon. So Frank's CO at the airport instructed him to attach tear-gas canisters to the runners of the Huey, wiring them into the cockpit so he could release the gas while flying: "when the students are protesting, fly low over them, release the gas, and the rotor-wash will take the tear gas down into the crowds and disperse them." Frank went into his office, wrote his letter of resignation from the reserves, effective immediately, and put it on his CO's desk.
[Frank's CO, incredulous]: What's the deal, Frank?
[Frank]: "I can't teach them in the morning and gas them in the afternoon, sir."
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