Advice on learning vertical reference landings
 

Hey guys, I recently started trying out a few vertical reference landings I.e landing my heel on a spot. Sometimes i seem to get it and other times it’s impossible! Besides experience and practice can anyone offer any insight or tips that might help. I’ve done a lot of dabbling in trying to understand the aerodynamics of a helicopter when operating on the air cushion or just a few inches about the ground but not much can be found. Any tips or advice would be greatly appreciated. Thanks in advance

From an old friend (170'):

“Take a CD marker pen and put a few straight lines across the skids and cross tubes, anywhere you think will be in your peripheral vision, when looking straight down at the hook. Maybe mark each line with a number, say 1-10 along the skid and A-J along the cross tube…

Go into an OGE hover (or have another pilot do it from the other seat) and look down at the remote hook. In this perfect hover, the hook might hang at the imaginary intersection of lines D cross-tube and 5-skid. Hold the hover, and try to imprint this sight picture in your mind, with the aid of the index marks. Remove the ones you don’t need on the next landing and in future, anytime you’re told to “ fly the hook, not the helicopter”, fly the sight picture, not the helicopter!”

Hope that helps

phil

paco,

I do not think he is talking about vertical reference like you and I know it.....He is talking about a "heel" which I assume he just means landing on a spot.

Are you trying to land on a dolly or some unique spot or are you just trying to figure out where the heels of the skids are on the landing gear as you touch down?

I am thinking what you are trying to do is learn "the ability to know where the heels of the skids are...." which is a learned ability that comes from practice.

An example....until I developed the "feel" for the Chinook's aft landing gear position....landings were easy enough if they were on a somewhat smooth flat area.

Later on....I was able to place the Aft Gear wheels on a Rice Paddy Dike without coaching from the crew.

I also "learned" where the Cargo Hook was.....and could put the Hook into an up held sling donut without coaching from the crew.

I cannot tell you how it happens...but in time you will pick up that ability and it is just a learned ability that comes to you over time.

I also advocate visualizing exactly where you are going to land the helicopter starting with the very first reduction of Collective as you begin your approach to your landing site/airport/helipad.

Then keep that visualization going until the aircraft is firmly on the ground.

That will make for better approaches which also make for better landings.

Weads,

You are on the right track and need to investigate "further effects" of controls and what is happening in "ground effect" among other things.

FYI it is described as "ground cushion" but actually there is no such thing.

The classic aircraft that stumps people in characteristics to fly smoothly is the AS350. The design accentuates a lot of the effects and you see people fighting them constantly when they are all "pilot induced".

With few exceptions 99% of all landings are slope landings. Understanding what is going on with the aircraft and a bit of practice and its a no brainer.

Shell out for Ray Prouty's books for a start.

Weads, pace out the distance between your pilot seat and the heel of the skids, measure it and practice walking around dispersal (or even a parking lot) trying to visualise that distance behind you - place your self in a particular position forward of a line or other marker (without looking at it) where you think the skid heel would be and then measure how far out you are. The more times you do this, the better your judgement should be.

We used to encourage pilots to do this to help assess where the tip path plane was so that their judgement of how close the tips were to trees or cliffs improved.

It's the same as learning to park your car or squeeze it through a gap - practice makes perfect.

Weads,

Ray's books - Helicopter Aerodynamics Vol 1 & 2 are available all over the place these days -

Amazon in hard copy paperback.

Apple Books electronic.

They are published by Eagle Eye Solutions LLC i.e. Shawn Coyle.

To have complete control of the aircraft you need to understand what is going on. Too much training these days is just based on "rote" and the details are missed or not understood.

You should have the ability to control and land the aircraft as easy as parking a car as per Crab and most people do. You can do it the hard way by "practice" or understand what is happening beforehand.

Ray's books are worth every penny.

https://cimg7.ibsrv.net/gimg/pprune....2e874e0a4f.jpg

Used to do this every day for about 9 months. Use visual references on the truck to do it.

The pilot of the UH-1 is using vertical reference to put it on the trailer. If you want to try it, pull the door on whatever you're flying and practice picking it up and setting it down while looking out of the door at the skid toe. You'll probably over-control at first, but you'll get the hang of it. Once you do, lean out a little farther and start using a reference farther back and under the aircraft, when you get better hang a line and start flying the hook:)

Not a good example. That looks like a Bell 205. And as many of us know, they tend to land themselves, and where they're supposed to, and without requiring much thought or effort from the pilot.

Gordy and LRP are right....the closer in you look the harder it is not to over control.

Picking up reference points, and shifting your scan as needed for alignment and distance is the key....height can be done by braille once you are positioned properly.

As to Gordy's photo....what he means is he drove the truck and backed under the hovering helicopter.

One trolley I landed a BO-105 on after every flight was very small and did not leave a lot of room for error.

Fore and Aft we were very constrained in that the aircraft had to be well forward on the trolley so the hanger doors could close behind us after we were winched inside.

To aid that....we used an ATV Fiberglass Warning Pole....but removed the flag and added a Tennis Ball.

The trick was to touch the Tennis Ball with the nose of the aircraft.....and a trick it was as the fiberglass rod was very flexible and wallowed around from the down wash.

Over time it became second nature and was not at all difficult unless we had a really strong gusty wind blowing around the hospital building.

Hahaha! Awesome story - thanks for the morning laugh John!

Reminds me of the A6 towing a target for RIMPAC live CIWS shoot when the Japanese CIWS walked up the cable and shot down the A6...off Hawaii...

https://cimg7.ibsrv.net/gimg/pprune....4e18551565.jpg

Had my co-pilot in the right seat for his first forecastle transfer - he did a couple dry runs ok, but started to go squirrely on the live hoist. Had to take control and put the man on deck cross-cockpit. Basically looking at the bridge windows, which were moving up and down of course...and backwards at 15 knots. Brain to hand interface near 100%...LOL.

This was long before I got to SAR boat hoisting off smaller boats...in the dark and worse wx, but at least we weren't flying backwards.
Google photo btw - not the event.

John,

A BK-117 with no SAS......known amongst the EMS crowd as the original "Vomit Comet" due to the things instability.

We tried doing it with just the Mark I eyeball of the Co-Pilot trying to look down but the Test Folks nixed that for lack of accuracy.

So after a Coffee and some brain storming....I suggested using the FLIR and we tried that and our success improved but still not good enough.......then we realized we had to compensate for the hover attitude of the aircraft and slew the FLIR to an appropriate setting aft of FLIR vertical to achieve "Aircraft" vertical and it worked way better.

It was very hard work....looking out on NVG's....listening to the CoPilot's steering commands....sneaking a quick look under the NVG's to the FLIR screen to see where the cross hairs were pointing....remembering they slid around depending upon the movement of the helicopter both in a horizontal plane but in all the other axis as well due to the control inputs and turbulence of the Out of Ground Effect Hover and wind speed variations.

It was a large smoke stack.....but it would have gone a lot better and easier had it been the size of a Cooling Tower not so far away!

The hole got very small when looking at it from three thousand feet.

Now instructors are lucky to have 500hrs and with all the PC tick the box parade going on, a training helicopter is lucky to get off an airfield... other than that, all good...

https://cimg4.ibsrv.net/gimg/pprune....3dae8490c1.jpg


Getting to the OP, it would seem to be advice on trolley landings? All ours were marked fore and aft with skid lines to give reference when lining up from behind, then a marking to where the cross beam should be when on the trolley.

Always approach from well behind and 'hover taxi' into the trolley keeping a reference ahead that aligns your eye view to where the skids should be: don't over-reference the markings at this stage.The reference may vary day to day depending on where the trolley is parked. When at the approximate position fwd, look out to ensure the skid is aligned and the crosstube is up to the appropriate mark, then down on the collective while using the yaw pedals to keep aligned with the fore and aft lines. Practice makes perfect, but a smaller trolley will inevitably cause loss of reference when the nose of the machine goes over the front!

Aids already mentioned (if it's a small trolley) are the glassfibre rods either side of the eye line, but cap the tips: one pilot at Essendon managed to punch the tip of one rod through the side window of an AS355.

All my pilots would have little problem aligning the machine this way, even my non-SAS BK117 could be plonked onto the right spot time after time. If the approach is tight and a more vertical approach needed, then kick off to the left to give a better downward vis out of the side window, then pedal turn to straighten up when a few inches off the deck.

Re SASless' tale of derring-do in a BK, we would carry out lighting checks at night for Melbourne Airport in the BK117, requiring OGE hover with small moves to check the TVASIs and other approach lighting. Talk about being in a black hole out to the west with absolutely no ambient light!

To John down under...."derring do" is not how I described what a right royal pain in the butt that Task was over two nights for me and one other crew.

What really made it fun is the powers that be would not tell us "why" we were doing that.

I surmised it was because some prick's wife said she was having an affair with a helicopter pilot and he was having some revenge.


Brother John,

While working for a very large oil company in the Middle East....which had its own Flight Department operating under the FAA Registry and Regulations.....I felt the need to choose a proper Room Name for use at pprune.

We were flying night VMC offshore in Non-Stablized 212's as the management (all former PHI guys) had cancelled the Sperry Systems that the aircraft had been spec'd with in order to cut the purchase price as they felt air conditioning was more valuable.....until they discovered the performance decrease....and then removed the Air Conditioning.

Leaving us to really sweat due to both the heat, humidity, and exertion flying in the pitch damn dark with no horizon in an unstabilized 212.

The management took the position that despite being offshore in the dark with no horizon or surface lighting for much of the legs....as the weather was VFR....we were VMC and not IMC.

Thus, my choice of "Sasless" was made....to remind me of just how utterly stupid some people can be.