I suspect that this will only be a viable procedure until the inevitable accident that causes a helicopter crash, then it will be deemed too risky for regular use (unless the helicopter can be unmanned)
I have friends in forestry, and their industry routinely uses helicopters, despite the risk, for a much lower ROI. Below are some videos of a christmas tree farm and a remote logging operation. I can't imagine that what rocket lab is attempting will be anything short of 10-100x safer.
How about helicopters lifting things from the street to the roof of a skyscraper? With the spinning blades mere feet from giant windows with people on the other side?
Forestry is a fairly low profile blue collar industry that doesn't get much mind share among the white collar people who think they're experts in how every industrial facility should run. You have the luxury of actually being able to make decisions by the numbers.
When you go into space numbers unfortunately tend to have to take a back seat to optics.
Someone crashes a log truck and nobody cares. Someone crashes a helicopter doing "space stuff" and suddenly every jerk who feels slighted that you didn't divert enough resources from your primary task (space!) to pander to their issue (your team isn't divers enough, your facility isn't environmentally friendly enough, your company vehicles aren't all EVs, etc, etc) along the way is happy to tell the news reporter or the Youtube head how you "have a history of playing fast and loose" or whatever. And then all the vultures who want to be seen "doing something" descend...
In those farming/logging videos, the helicopter is picking up stationary objects and depositing them in a desired location. I have trouble imagining that catching a moving object would be less dangerous, except to the extent that the pilot's job is only to catch a single thing that day, not move dozens or hundreds of individual objects.
(Those loggers though in the second video seem like they're standing awfully close.)
Both are very hazardous under different risk models.
There's a concept in flying stuff that you always want to be "three mistakes high" (I think this is credited to Gene Gottschalk although I have no idea if he was the true origin - it's taken a life of its own in many communities). By that logic, the Christmas tree pilot is at a very sub-optimal altitude - 0.75+ mistakes high, but still high enough that they're unlikely to make it out in the event of a mistake or catastrophic failure.
The retrieval helicopter is presumably several mistakes higher and more likely to recover from simple mistakes or equipment failure, but runs the risk of being smacked by a flying object.
Neither are safe, but I think there are mitigating factors to the rocket collection that aren't present in the Christmas tree video. I think they're closer to even risk-wise. If I were a helicopter pilot, I'm not sure I would want either job!
Yes, the target will be a moving object, but its motion will be steady and predictable. The helicopter and booster will be the only two objects in the area, and capture should be slow and steady when viewed from the reference frame of the copter that has matched velocity. Aerial refuelings look crazy from the ground but easy but from the pilot's point of view.
While you are probably technically right, I think you are over estimating the risks involved. The booster will be under a parachute, travelling relatively slowly, and there will clearly be many safety precautions and features involved. They will certainly have a stringent check list before proceeding with the attempt as well as some sort of fail safe cutting of the lies if something goes wrong.
I would expect the chance of a serious accident to be very low.
Also keep in mind these sort of mid air captures were well practiced by the US during the Cold War to capture returning photographic film from spy satellites. Although that was with airplanes not helicopters. A variation of it is actually shown at the end of James Bond Thunderball where he and the girl are rescued from a life raft via a balloon and capturing plane.
Helicopters bring more risks than airplanes. Helicopters with external attachments are notoriously risky (for aviation standards). Helicopters with external attachments that bring momentum independently of the main vessel are the kind of thing that looks way too risky.
An airplane would probably cope much better. And even then, the fact that the military do something is not a good reason to expect it to be viable for civilian use. Military applications tend to accept much more risks.
Remember that they've already been practising this for months - it's not a first time thing - by now they likely know and understand the risks well
(Also NZ is full of helicopter pilots who work doing "deer recovery", snatching animals with shotgun-nets, hanging them under helos and pulling them off of near vertical mountain ridges - grabbing something under a chute is likely easy in comparison)
LOL. Yeah sure, so the plan is to have something traveling at 800kph somehow intercept a falling rocket stage, catching it in a web or whatever and start dragging it along and somehow land safely afterwards?
The first mid-air recovery of CORONA spy satellite film canisters by a C-119 Flying Boxcar fixed-wing aircraft was performed in 1960. This is a well understood capability.
I see on your page you say "I take pride on behaving righteously and honestly". Don't forget also:
Be kind. Don't be snarky. Have curious conversation; don't cross-examine. Please don't fulminate. Please don't sneer, including at the rest of the community.https://news.ycombinator.com/newsguidelines.html
From wikipedia, it can land on as low as 120km/h. (That thing can be really slow, it's impressive.)
Still, I expect an empty second stage rocket to weight little enough that one can get by with a smaller plane, that can fly slowly due to its little weight, instead of sheer engineering feat.
To their point, I'm not sure how well a carefully controlled slow descent and catch interplays with an object that can never be in place, in fact, it needs to be at 200 kph. Sounds much less safe.
I can’t find its empty weight online easily, but this booster is quite a bit heavier than these film canisters were. I would be concerned about the impact catching it would have on the helicopter.
I guess the hook they use for catching it must be hanging from a somewhat line that deforms on impact, becoming longer while absorbing lots of energy. You don’t want this behaving like a heavy bungee jumper under your helicopter.
But that was in military context, with higher risk tolerance to loss of human life. (for getting intel, way more dangerous methods are applied all the time)
