Hoisting vs Underslung Humans
 

We spent a week with the Norwegian Air Ambulance Foundation talking about the recent scientific study they did between using a hoist and using the underslung method. Pretty indepth what they did - lot of scenarios in different locations.

Have a read and let me know what you think.

Hoist vs Underslung

The actual report is here: https://www.sciencedirect.com/scienc...25753525002218 I saw it a few days ago posted on LI.

One thing I'm curious about is why the doctor operates the hoist and the technician goes down to the casualty - seems more logical to do the reverse?

From 60+years ago;;Rotorheads forum Page 10,`Underslung loads in Emergency`page 2,#25-#40...

Hmmmm !
An interesting research programme, but ...............
My own experience 14 + years S&R and test flying with a variety of hoists and underslung loads, points unerringly to the hoist, with the add-on 'long-rope' where needed. By their very nature, these operations are unpredictable and ad-hoc variation for each crew member has to be allowed for.
My reluctance in respect of HEC stems from unfortunate (but non-fatal) experience with Whirlwind and Seaking - the common factor being the attachment hook. The hook mechanics, theoretically, prevent uncommanded release - experience refutes this, as it does for trials flight HEC (with dummies ! ! ! )
The hoist referred to in the programme is not one I have come across, but there is sufficient variation in manufacture available to suit most users.
As to the deployment of medic/winch Op/ winchman discussion, while we operated 'in role' normally, provision was made for winch Op/winchman reversal if the situation merited the relative experience.

PS - The fact that this is Norway oriented makes an obvious 'local' influence (terrain and Wx) but, even so ...

One of the big take aways for me was that there are still organisations out there willing to spend the amount of money required to objectively investigate and answer a question. Great to see and hopefully an example for others to follow.

The Foundation has an annual budget of approx $25mil Euro to do all these research projects and they are always looking to delve into things.

They had always been asked by people which option is better so they decided to rather than just use personal opinion they would use actual stats.

Personal experience over the years and empirical evidence of a few "clusters" would indicate that Hoist Ops doesn't get the respect that it deserves to keep the operation safe in some cases. Theory and logic doesn't quite cut it.
Was at a reputable operators facility once doing maintenance in their hangar and casually asked if they trained for "roll out" on their hooks etc. The look on the faces before and after a demonstration was interesting.

RVDT,can you elaborate terminology../?

I imagine RVDT is talking about dynamic rollout. Where a closed and somewhat secured hook can still be opened during various manipulations of the attachment on to the hook.

This is a very interesting piece of work and one I’ve been waiting for. Thanks Ned for sharing.

What Jabberwocky says. Some info here but plenty more if you search: https://lifesavingsystems.com/videos...HemZeKxVQb0uOP

Royal Australian Navy learned about this risk the hard way with a fatal fall during hoist ops with an S-70B-2 on 20 Dec 1995. For details, see for example: https://www.faaaa.asn.au/wp-content/...AALetterv2.pdf (this fatal accident doesn't appear in the ASN Wikibase yet).

I have a memory of reading about a much more recent Australian case of dynamic rollout reported by the ATSB which I thought also related to hoist operation, but not sure how to search for it now. The only ATSB report I could find easily was for a sling load case: https://www.atsb.gov.au/publications...on/ab-2020-023

Dynamic rollout was one of the reasons we typically tried to avoid bellyhooking in HUSLE ops in favour of a strop with a swivel at both ends. More consequential when dealing with live HEC though!

Thanks 212 and Jabby,I think on RAF SAR,this was a `known` fault with hooks but was mitigated by having a `pip-pin` attached ,on a wire,and then put into a hole in the `gate`,so it was locked.Maybe `Crab` or CJ can comment on later SAR times..
For the SAS troopers lift,I attached the abseil tapes,looped/double knotted to the winch hook,so we could winch if the trees were very high,as it was originally a pick-up from an LZ,but they(SAS) DIDN`T GET TO IT.
The later night pick-up of the stretcher/wounded had the tapes secured inside to the floor cargo tie-downs.Never to the cargo hook.

Sycamore - Exactly so. There were other add-ons, such as the 'Grabbit' hook and the short extension strap and. for anything over 60', the long strop (and then the later 'high line') Each had potential problems but personal experience made the underslung hook an absolute 'no-no' for human carriage.
Hoist problems (for the Whirlwind) stemmed, originally with 'bird-caging' ( wire strand separation caused by uneven cable laying). This we cleared with the introduction of the Lebus drum.
Ground and air testing of a limited number of other hoist manufacturers' products showed what improvements could be made, but (as ever) finance dictated the choice ... as with the RN Lynx. ! ! !

Coincidentally, or not, I was the PiC of the flight you linked, in your reply to me…

Coincidence! ...and good it wasn't a human load!

Absolutely.

I came across a further recent example of an uncommanded release of an external load involving VH-UAK, an AS350 B3 in Fiji on 1 September 2025. The ATSB is assisting the CAAF in Fiji with looking into this case. No further details of circumstances as yet:

https://www.atsb.gov.au/publications...rt/aa-2025-002

If you have a person on a hoist with a hoist operator - in the event of a problem you have two choices; winch them back to the cabin or cut the cable over an area you can see to be safe at a safe height and speed.

If you have a person underslung you have only the latter.

The other difference is that with a hoist operator, you have one person concentrating on flying the aircraft and another concentrating on looking after the person on the wire.

With an underslung person you have one person trying to do both.

You pays your money (or tries to save it) and takes your choice.

Think the last few posts on lost loads must not be compared to this setup due to great differences in the hardware used.

This operation is using dual keeperless hooks(must be opened to attach a load) with separate release mechanisms, and at least one of the linked cases above involve older type load beam with spring loaded keeper single hook, combined with oversized rings which is not an issue with keeperless hooks used in this setup.

It is an apples vs oranges discussion.

I found live hauling people to be the most stressful flying I have done....done in a Huey while single pilot.

It was not the flying that was difficult but rather the stress imposed knowing the ramifications of getting it wrong that weighed upon me.

The people were total strangers but none the less important to their families, friends, and co-workers.

The decision I made was their safety came first....then mine....then the aircraft.

I have always viewed the aircraft as a reusable but expendable metal container designed to be used for the protection of the occupants there of.

Add a 150-200 foot long line with 5-6 human beings on the end of it....and that multiplied the difficulty level by a couple of orders of magnitude.

Canadian Rockies with Alpine Helicopters a couple of years ago....
(oooops.... more than a couple... my bad...)