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-   -   Helipads - round or square? (https://www.pprune.org/rotorheads/564151-helipads-round-square.html)

Squawk7700 6th Jul 2015 23:59

Helipads - round or square?
 
I was mindlessly driving along the other day thinking about this....

Are the majority or landing pads round or square?

Is there a reason why they are seemingly often round? Is that a design element to do with rotor-wash?

eg. Hospital landing pads, ships, oil rigs etc. I'm referring to raised pads, versus ground level.

grumpytroll 7th Jul 2015 04:44

Cost and strength
 
Bottom line is that building/constructing most anything is easier and cheaper if it is square as opposed to round. Not only the pad itself but the underlying support structure. I have seen very few round landing pads. The ones I have seen that are round are generally painted round shapes on the ground or painted onto a squarely constructed structure. I have seen some round and lovely rooftop pads. They look nice.

Cheers

John Eacott 7th Jul 2015 05:54

I've no idea how the majority are shaped, but I strongly favour round helipads. The anal compunction of some drivers to align their machines (especially skid equipped) with the edge of a square pad regardless of the wind direction is notable. Back in 1984 I managed to have the pad at Albion Park painted as a circle for this very reason, and I noted last time that I was there it is still a circle!

Dancing around with a 20kt crosswind trying to line up with deck edges is daft, IMO. Or even plonking the skids along the lines of the 'H' :hmm:

Flyting 7th Jul 2015 06:10

Here by me it's a mix, and looking at it, it looks as if it was decided according to the building design underneath the pad.

...and as for...

The anal compunction of some drivers to align their machines (especially skid equipped) with the edge of a square pad regardless of the wind direction is notable.
I looked underneath some of them and all the strong structure support is in the middle of the pad and not at the sides. The pad is designed for ONE helicopter (CAT A) at a time, so be carefull where you park your bus...

TheiC 7th Jul 2015 07:56

A square pad provides much better close-in visual cues for control in yaw. This doesn't mean you have to put the skids parallel with the edges. In a feature-rich environment, it may not matter, but in isolation (top of a building in haze etc) it could be important. From a purely aesthetic point of view, I like hexagons.

ShyTorque 7th Jul 2015 08:06

The one at LHR is triangular. Now how confusing is that? :ooh:

Seriously, though, it's not a big issue what shape it is.

diginagain 7th Jul 2015 08:49

The one at my current place of work is octagonal, as were the last three or four.

TheiC 7th Jul 2015 09:14

It just occurs to me: if it's pentagonal, what will the OCD-suffering parallel-skid brigade make of it?

jimf671 7th Jul 2015 09:24


Originally Posted by John Eacott (Post 9037194)
I've no idea how the majority are shaped, but I strongly favour round helipads. The anal compunction of some drivers to align their machines (especially skid equipped) with the edge of a square pad regardless of the wind direction is notable. Back in 1984 I managed to have the pad at Albion Park painted as a circle for this very reason, and I noted last time that I was there it is still a circle!

Dancing around with a 20kt crosswind trying to line up with deck edges is daft, IMO. Or even plonking the skids along the lines of the 'H' :hmm:



Originally Posted by TheiC (Post 9037297)
A square pad provides much better close-in visual cues for control in yaw. This doesn't mean you have to put the skids parallel with the edges. In a feature-rich environment, it may not matter, but in isolation (top of a building in haze etc) it could be important. From a purely aesthetic point of view, I like hexagons.


Planning for redevelopment of a helipad soon. It is definitely in a 'feature-rich environment', so round it is then. :ok:


(Not that I'm saying the guys are anal!)

SilsoeSid 7th Jul 2015 10:13


Shytorque;

The one at LHR is triangular. Now how confusing is that? :ooh:

I hope you will read the AIP before parking there, as the triangle you are referring to is a helicopter aiming point located on a taxiway area :ugh:


EGLL AD 2.20 Para 5 :ok:


5. Helicopter Operations
.
.
ii. The helicopter aiming point is located on the taxiway area east of Link 43. It is marked with an 18 m sided triangle with a conventional 'H'. This aiming point is lit and available for use throughout operational hours. The take-off and climb surface has been protected to 8% to the east and west of the aiming point (see Chart AD 2-EGLL-4-1).

iii. Caution must be exercised when using this aiming point which is on a live taxiway.

iv. Helicopters alighting at the aiming point will ground or air-taxi to the parking areas as directed by ATC.

v. In circumstances as detailed in AD 2.22, Flight procedures, paragraph 9, visual separation will be applied whilst the helicopter is in transit between the holding point and the helicopter aiming point. In all other circumstances, standard separation will be applied.
http://i52.photobucket.com/albums/g1...psynzvququ.png

http://i52.photobucket.com/albums/g1...pst8az8c0p.png

Um... lifting... 7th Jul 2015 11:37

Indifferent as to what shape they may be, but one prefers them flat on the top.

jimf671 7th Jul 2015 12:08


Originally Posted by Um... lifting... (Post 9037508)
... one prefers them flat on the top.


Noted. :ok:

Vertical Freedom 7th Jul 2015 12:21

I want a Star to land on :eek: a Gold Star :ouch:

ShyTorque 7th Jul 2015 12:41

Sid Said:


I hope you will read the AIP before parking there, as the triangle you are referring to is a helicopter aiming point located on a taxiway area :ugh:
No-one mentioned parking on the triangle at LHR because no-one can, but although it's known as the "HAP" it is surprisingly the only helipad at that airfield. I land there probably more often than most (now at about £4500 a pop, not many folk bother). Arriving helicopters are held off to the south of the airfield by ATC until the taxiways are clear. After landing, helicopters are directed to taxi away behind the "follow me" vehicle. We normally park on the Royal suite, although sometimes other stands are used. Departing VFR helicopters are required to taxi back to the HAP, which is much better than having to join the queue for the main runway, as we always had to do by night some years ago.

SilsoeSid 7th Jul 2015 12:52

So, the original question was; "Are the majority or landing pads round or square? ... I'm referring to raised pads, verus ground level."


After many posts about aligning machines with pad edges & 'H' markings and mention of multi parking on the pads, Shyt answers with, "The one at LHR is triangular. Now how confusing is that? :ooh:"

Very confusing especial as it is at ground level, glad my link was useful though ;)


We'll ignore the remark; "… it is surprisingly the only helipad at that (LHR) airfield."

John R81 7th Jul 2015 13:20

Mine is round because.... When I built it, that's what the excavator shovel could reach. Size & shape therefore determined by the deigners of the Volvo 25 Excavator.

Just like train track dimension was determined by the width of 2 horses bums. (Strange, but true)

TRC 7th Jul 2015 13:50


......... was determined by the width of 2 horses bums. (Strange, but true)
You must have some skinny horses.
It is supposed to originate from the required distance - track - between the wheels of a cart to allow enough room for a horse to fit between the shafts.

ShyTorque 7th Jul 2015 19:29


Very confusing especial as it is at ground level, glad my link was useful though
You're easily confused then, Sid and as usual, a legend in your own tea break.

Feeling the need to big yourself up again? :rolleyes:

SilsoeSid 7th Jul 2015 20:26

Shyt, reread the post you quoted from please.

It was you that was confused about triangles in the first place.
Embarrassed about being caught out about the detail of the LHR triangle and now trying in vain to dig yourself out by any chance!

Bigging myself up! Far from it, just getting the facts right.
Thing is, I know my place, as lowly as it may be to you, while you keep having to tell us yours.

whoknows idont 7th Jul 2015 22:24

Excellent thread so far! :ok:


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