July 2022
Yes, rotorwash can be a problem. In Hawaii in the late '70’s my Infantry unit was in the field and a young soldier was standing atop an M561 Gama Goat holding up the sling to hook up to a hovering CH-47. When the aircraft was at the correct position the soldier was blown OFF the Goat. He shook himself off, got back on the vehicle, and completed the hookup. Later. after I got out, I eventually received my A&P and always remembered that incident when I worked at PHI in Louisiana.
July 2022
Having once been “rock and rolled” on a hold short while a Chinook landed in front of me…
NOT a “bash the controllers” point - but an observation. Controllers need to think “outside the rotor disk” too.
Cleared to land on an 8,000ft runway in a thrifty, nifty, 150 - I simply didn’t want to be anywhere near the taxiing Blackhawk on the close parallel taxiway as I flared. I announced: “landing long after passing the taxiing helicopter”. I then powered up to hold about 250ft as I passed the helicopter and then continued to land once well past. It was over so quickly that the tower controller’s acknowledgement of “Oh - good idea - cleared to land long” wasn’t out his mouth before I was flaring for the real landing. With an 8,000ft runway it was possible. If it had been a shorter runway - a go-around would have been in order.
July 2022
These autonomous flying taxis must be approaching the 4 tonne mark of the Huey – big batteries four motors and rotors, and four passengers who put 80 kg on the form when 100 kg will be accurate. (Not joking, ask anyone who has to weigh people these days…)
Maybe municipal parks departments will site the landing pads where the downdraught will do the most good in clearing leaves in the autumn.
July 2022
These autonomous flying taxis must be approaching the 4 tonne mark of the Huey – big batteries four motors and rotors, and four passengers who put 80 kg on the form when 100 kg will be accurate. (Not joking, ask anyone who has to weigh people these days…)
July 2022
Note to self: Three rotor diameters PER ROTOR is not unreasonable… just sayin’…
July 2022
Lucky or good? A quick review of the relevant research and analysis shows that luck has an unacceptably high failure rate.
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July 2022
I don’t like mixing rotary and fixed wing at all. At peril of accusations of discrimination, the more correct term being discretion, rotary and fixed operations should be separated at airports with the real estate to accompany this. It just makes sense.
July 2022
Second that on separation of rotary wing and fixed wing! Also, helicopters practicing autorotations to a runway occupy the runway for too long, in my experience. (I’ve seen gliders do the same thing…)
A few months back, I walked by a CH-53 that was on the ground, rotors turning, idling. The downwash from that big bird was very strong. I’m not calibrated for winds that strong, but I try to avoid helicopters on the ground, too.
July 2022
So here’s a question, and hopefully not an invitation to trolls. At some point, electric vehicles will be appearing at airports. Eyeball engineering says that less disk area (summing up all the disk areas of the rotors) could (weasel word) mean higher downwash velocities, and more hazard.
Has the FAA considered this? Has anybody?
July 2022
I decided to visit The Promenade in Brooklyn a few years ago. A nice sunny day for a walk by the East River looking out to view the lower east side of Manhattan. Tour helicopters are everywhere, taking off from the East side helicopter pier when they all disappeared. Looking towards the Hudson river by Battery Park, V-22 Ospreys came into view and one by one landed on the empty pier. Each one with green paint, no markings. On the street side of the pier, black suvs with lights on, possibly a visit from potus to a private function or U.N. meeting? At least two Ospreys landed, maybe three but I counted five in all. Lifting off, the departed south towards the Hudson heading south. Had binoculars to view it all. No one blown away from rotor wash, dresses flying up, etc. Couldn’t find any local news covering this surprise event, possibly deliberate to provide as much secrecy of the potus visiting any public area. All this took place in probably less than an hour or so. Having not flown in many years, I forgot TFRs were probably put up for that late morning/early afternoon VIP visit to NYC.
July 2022
I learned to fly out of Elmendorf AFB in the early 70s, and many of our “sorties” in the 150s were to Fort Richardson’s then towered single airstrip. In fact, that’s where I solo’d. I remember early on my instructor warning me to beware of two things, Beavers on skis and helicopters of any size.
I don’t know where the 3x the rotor diameter thingy came from, but in my view, that’s not enough. In recent years, I’ve been pummeled by the helicopter down wash of a relatively smallish Bell that was hovering a goodly distance from the taxiway, far more than 3x the rotor diameter, as I taxied by. I’ve watched a civilian Huey toss large portable plastic barriers around as he hover-taxied—because one of those barriers nearly hit my tied down airplane, its pilot and I had a relatively pointed discussion after he set down. He had hovered directly over a line of parked aircraft (including mine), all of which were fortunately tied down, without any recognition of the potential for damage he had caused.
A situation similar to the one at Cable involving an ANG Blackhawk and a Cirrus at KFNL a few years ago had the same results—and again a trashed airplane without serious injuries to the pilot. My observation is that helicopter downwash is less predictable than wingtip vortices—and those aren’t nearly as predictable as the FAA would like us to think.
So my personal practice has evolved into avoiding being anywhere near any size helicopter. I’m happy to get out of the pattern, or if I’m taxiing, to hold in place, to avoid being blown around. It’s not worth pushing it.
July 2022
I flew helicopters for the US Army for over 20 years. It never ceases to amaze me to see helicopters, especially single engine, hovering around at twenty or thirty feet above the ground. When I first learned how to fly, it was in the OH-13 E & G models, admittedly there were some engine reliability problems, but we were taught to hover 2 to 5 feet above the ground. There were reasons for this, 1) develop and maintain precision hovering skills, 2) when the engine craps out, not if, a successful hovering autorotation is far easier from three feet +/- than twenty, and 3) the rotor wash is much less at the lower altitudes (safety for others in the near vicinity). Had that Huey hovered across the runway at three feet, the Cessna 210 “may” have been able to successfully complete his go around. Just another point of view.
July 2022
I recall watching a POTUS, Nixon I think it was, arriving by VH-3 at the ABC studios in Hollywood, which were embedded in a residential area. The smooth and deliberate low angle approach created a fairly impressive trail of flying dirt, dislodged landscaping and a considerable amount of roofing material from several homes. I spoke with one of the advance crew after the excitement died down and his comment was “yeah, well, it’s part of the cost of doing business.”
July 2022
Key point, separation should probably a minute or two, just as you would want from a transport aircraft. Unless perhaps the video is sped up, I counted 15 seconds from the helicopter crossing the runway to the arrival of the Cessna over the runway.
1 reply
July 2022
Correction it’s 21 seconds per the counter.
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July 2022
I have my plane in a hangar at an airport near Houston, Texas. I am in the middle row of five rows of hangars separated by about 75 or so feet. A couple years back, a guy had his Robinson helicopter in a hangar across from mine and down two units. When he would take off, he would pull the 'copter out, close his door and start up, taking off from between the rows. On returning, he would descend to about 10 feet at the end of the row, then slowly move down to his hangar and land. Trapped between the hangars, the amount of down wash created from the small Robinson still blew all sorts of dirt and debris into my hangar and blew things around inside my hangar. I can’t imagine what a larger 'copter like a Huey or Blackhawk would have done in the same situation. Fortunately he moved out and went away within a couple months. Not sure if it was his idea or the airport’s.
July 2022
Always sad to see a broken plane… and they never seem to fly straight when ‘fixed’…
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July 2022
Same happened to me (though, without the crash) back in 1997 at KGFK. I was fortunate enough to have enough airspeed to fly past the rotor wash, but I ran out of both aileron and rudder, and was still rolling to the right. No mention by local controller that there was a hovering helicopter ahead and to the right while I was taking off. That one went in the “luck” category. Years before, I was almost blown off the taxiway by a Saab 2000 conducting a full static run. Again, no mention by ground controller. I’m hyper-aware of my surroundings now.
July 2022
Some time ago at KPDK a S76 helicopter was crossing over mid field to land… with a Cessna taking off below it… the Cessna was swatted out of the sky.
Always pay attention to helicopters if you are in a small plane. It is as bad as flying behind a 747.
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July 2022
▶ system
This is the wrong conclusion to draw from the data. Where luck prevails, nothing happens and everyone goes home to eat dinner. This happens far more often than accidents do. Any rate involves both a numerator and a denominator; the denominator in this case for a “luck failure rate” is massive and mostly unmeasurable.
July 2022
▶ system
Yes the 140 was powered up for go around when he hit the wake. The Helicopter crossed the runway in front of him unannounced when the 140 was on short final. Read the pilot report. It is well done.
July 2022
▶ Richard_G
The problem is that helicopter behavior is often erratic and unpredictable, not to mention unannounced on frequency, as in this case. If the helo blasts across an active runway when you are on short final, you cant go left, cant go right, and with 85hp you cannot get above them if they are at 30 feet instead of 5 feet like they should be. I was lucky to get under one, but probably only escaped by a second or two on short final. There should be a database for reported near misses - it would dwarf the number of accidents.
July 2022
▶ Richard_G
They fly plenty straight if the rebuilder has a straight jig and the required skills.
July 2022
▶ system
Helo was originally on the south side of the runway and appeared to be landing there. Then he decided to land somewhere else and crossed the runway in front of the 140 on short final to land on the north side.