Merlin info

[DucatiST4]

Maybe on odd question but i work for an architects practice and we are currently working on the design of a new fire station in the Peak District. One of the requirements we have to meet is that there is space to land a Merlin helicopter (mountain rescue etc). Its proving very difficult to find the information that we need.
Anyone got any links or manuals available that might help or are any Merlin pilots able to advise?

Many thanks.

Paul.

[VfrpilotPB/2]

Paul,

You will find that the Merlin is about the same size as the Hughie or UH1 but I think it has four blades not two and they are on skids and more heavy, many people will be able to give you dimentions, if I was at home I could but Im not so I cant. SASLESS will give you all you need to know on dims about the UH1


Whatever you do, give the pilot plenty of space, away from trees and building and flagpoles and wires they tend to do silly things to Helis and spoil days.:ouch:

Peter R-B
Vfrpilotpb/2:ok:

[DucatiST4]

Thanks Peter. Yes we have the dimensions of the thing but presumably it needs more than just a clear space equal to or a bit bigger than the rotor disk? Would it decend and lift off vertically or do they prefer to come in at an angle so they don't decend into their own turbulance?

Trouble is even if we do find someone who knows the answer we'll still have to get it in writing before we are able to say go ahead, its a question of liability and all that legal stuff!

[HUMS]

Have a look at http://www.agustawestland.com/products01_07.php?id_product=7&img=dim_EH101.gif if you just want the physical dimensions ?

[Bravo73]

Paul,

According to BHAB, the EH101 (Merlin) is 22.80m long, has a rotor diameter of 18.60m and Max AUW is 14515kg. (But judging by your last post, you already know that.:O)

But BHAB also publish a very useful guide (http://www.bhab.flyer.co.uk/sitenew.doc) to setting up a helipad. If you haven't read it already, I highly recommend it for what you are attempting. If any of the language gets too 'heli technical', please don't hesitate to ask for clarification.


HTH

[DucatiST4]

Excellent link Bravo, that'll keep us going for a while.

Many thanks.

Paul.

[Daysleeper]

You will find that the Merlin is about the same size as the Hughie or UH1 but I think it has four blades not two and they are on skids and more heavy,


A post that is usless to the point of being pointless based on how a merlin is about 3 times the mass of a UH-1, is on wheels and is considerably larger all round, not to mention things like disc loading likely rotor wash etc.... so almost exactly not like a hughy in every respect.


Westlands should be able to provide advice , after all they build the thing. I'd be tempted to phone them up and ask (+44 1935 475222).

Some reading for you could include ICAO Annex 14 Volume 2 which although intended for licenced helicopter aerodromes includes a lot of guidance as to FATO (Final Approach/Take Off) clearances and required areas.
Also lighting and markings, surface materials etc.

The CAA in Gatwick should have a Civil Air Publication (CAP) covering similar UK requirements. (possibly 168 though that may just be fixed wing)

Speak with current UK Merlin operators - the RAF and RN and ask for their requirements.


I suspect the merlin requirement is because it is the largest helicopter likely to be entered into the competition for the UK's future SAR needs and as such a pad designed for a merlin should fit anything else.


Edited to add - Like the BHAB guide, consider also
FAA planning guide (http://www.dot.ca.gov/hq/planning/aeronaut/documents/5390-2b.pdf) Ok its american but it has nice pictures that make things more obvious.

[nimby]

Presumeably someone at RAF Benson must do/organise this sort of thing fairly regularly ...

[Sikorskyfan]

Paul,
You might want to check with the Canadians, they fly a variant of the EH101 in the SAR role (well sometimes). The Cormorant is very much like a Merlin Mk III in that it is non-folding with a ramp (actually it is exactly like a AW510, but that’s another subject). Anyway the point is as they fly the aircraft in the SAR role and therefore do a lot of landings in hospital parking lots etc. I would contact 442 Squadron in Comox, British Columbia, someone form there may be able to help you. Good Luck!

[[email protected]]

And you will discover that the downwash of the Merlin meant that the Canadians had to stop using some of their smaller LS.

An absolute minimum just to park the aircraft should be 1.5 times the overall size of the aircraft (blades turning, from front of MR to tip of TR) which if that dimesion for the Merlin is 22.8m gives just over 33m for the diameter of the circle.

For military use and inclusion in our HLS directory, the LS would need to be recced by MAOTS.

[DucatiST4]

Thanks for all the info guys, most helpful.

Re Westland, i though that they made them but unless i've got it wrong somewhere it turns out that Westland build the airframes, Rolls Royce make the engines and Lockheed Martin (UK) put it all together. We are awaiting a return phone call from them anyhow.

The BHAB guide is very useful but i'm not so sure how relevant it is to a military helicoptor which operates under different limitations to a civillian machine. More or less onerous? I'm not sure. Think its mostly related to single engine performance (in the event of an engine failure on a mulit engine helicoptor).

Any help as to what MAOTS is?

[airborne_artist]

You are best off speaking to the operators of the Merlin, not the makers. Call OC 28 Sqn (or 78 Sqn) at RAF Benson on 01491 837766 and ask him.

MAOTS:

"The MAOTS are a very busy unit that travels throughout UK and Europe to give advice to military and civilian organizations on the utilization of helicopters. There are 13 MAOTs, each one consisting of a RAF Officer, Master Aircrew or SNCO and 2 Signallers from 21 Signals Regiment (Air Support) based at Colerne in Wiltshire. The Teams regularly deploy on operations and exercises in support of the British Army and the SHF. Primarily the Teams co-ordinate and control helicopter movements into and out of the helicopter landing sites (HLS), and provide communications between the supported unit and the aircraft. When deployed the Team Leader (TL) acts as the trouble-shooter for all helicopter matters with an overarching responsibility for Flight Safety. As a secondary duty, TLs are also responsible for maintaining and updating the information contained in the various HLS directories in use by all military helicopters."

from http://www.raf.mod.uk/RAFbenson/aboutus/units.cfm

[[email protected]]

Paul, as AA has pointed out the MAOTS (mobile air operations teams) are based at RAF Benson in Oxfordshire and will doubtless give you any information or guidance if there are any of them actually in the UK at the moment.

As you rightly infer, military helicopters don't operate to public transport rules but that doesn't mean that we want to take unneccessary risks on approach or departure, just that we can operate more flexibly if required.

I don't have the NATO LS size dimensions to hand but I know the MAOTs will - the circle of 1.5 times the overall turning dimensions I referred to is what a military helicopter dispersal is supposed to have to operate helis from and is a good starting point as you want to keep people well outside the disc until the crew are ready for emplane/deplane.

You may be better off in the long run complying with the BHAB guidelines though since SAR may well be privatised in the future and any Fire Service helicopters (an ambition of some) may have to operate to public transport rules in some conditions.

[dangermouse]

33 fly Pumas, try 28 !!!

DM

[TRC]

I don't have the NATO LS size dimensions to hand but....

It would be a Size 5 for a Merlin - 15m hard standing, 60m diameter cleared to ground level, 100m free from obstructions, etc..

BUT, there are other things to consider too - approach angles day & night, etc.

Contact the squadrons, JADTEU & JHSU before you do anything else.

TRC

[SARBlade]

A few other things to consider that haven't been covered in enough detail are as follows:

Weight: true it is 14,500Kg AUW, but what needs to be considered is that on the Merlin variant there are only four wheels supporting this weight. Tire pressure is ~7 bar, so there is significant loading on these four points. Not sure what it is though, I only flew the thing ;o). Don't use gravel or loose particles, see area below.

Size: As mentioned above it needs plenty of room, if the helipad is for patient transfer, the approach is and landing is not always conducive to a good ramp to ambulance meeting. The pad should be large enough to allow the pilot to "castor" the aircraft. That is, to turn the aircraft on the ground about its main rotor mast (or there about).

Approach & Departure: Although most helicopter pilots will use the wind to there advantage, the 101 does give excellent out of wind performance, try to set up the helipad approach with the best wind advantage. If the aircraft is flying under military specification then Cat A performance may not necessarily apply, however, if under civilian certification then this will have to be taken into consideration. Again, Westland can provide this info, I don't have a RFM in front of me to give you the details on helipad approach and departure to meet Cat A specifications.

Area: While it is important to take size into consideration, the affect of rotor downwash is significant! I have blasted autos with sand picked up from a road running adjacent to the pad. Not good! A wind sock was blown down at a hospital pad by a fellow pilot I worked with. The wind generated is significant. Rotor diameter is 18.5 m, this may be holding 14,500 Kgs in the air! Grass is good surrounding material, not small trees or shrubs. Large coniferous trees can be pushed over, even on approach.

Lighting: Standard helipad lighting is enough, again, whether or not it’s a military operation or civilian one, NVGs will aid the military operator but not the civilian one (not sure on that however), so this will refer to approach and departure for night operations. Oh, and have the wind sock lit ;o)

Noise Abatement: The 101 is loud! It has three engines operating plus the whistle of the two rotors. Having a pad away from sensitive areas is crucial. Pilots can shut is down for this though.

Support: The 101 does not need anything special in aircraft support equipment, however, having the usual helipad gear such as fire extinguishers, two-way radio communication, have frequency visible to pilot as he flies over or published. A well written operation manual for persons at the helipad for 101 danger ares, how to approach, etc.

I can't think of anymore things at the moment, but this will get you started as others have given good information regarding contacts in the UK. As I am in Canada, I can't give you those things; however, Sikorskyfan has indicated 442 Sqn in Comox, BC. Ph 001 250 339 8116



Enjoy :)

[chevvron]

Go straight to the top and contact Colin Hague at Westlands, Yeovil. He's a good bloke (chief test pilot) and I'm sure he'll advise you.

[SARREMF]

You have a PM

[dangermouse]

It's now Don Maclaine, but I suggest you don't contact him direct but go via the Flight Ops dept or through customer support at Yeovil if you want to talk to WHL direct. However the good advice you have got here is probably correct in that the squadron is more likely to be able to answer specific operational questions than the design authority.

RAF Merlins are now cleared to operate at 15600 kg (albiet with twin wheels on the main gear) rather than 14600 kg like the CSHs so that may be something to take into account, although if you are going that big why not scale for a CH47 to cover all UK aircraft types?

Dont assume that the aircraft is NVG compatible, RN aircraft aren't but I guess that covers other platforms as well


DM

[Sikorskyfan]

Paul,
Helpful group huh? I hope that you are not getting information overload? Actually it is heartwarming to see how people can all pull together and offer up valueable advise to someone that is trying to achieve something that is worthwhile. I think that you are going to have one fine Helipad at the end of all of this.

Best of Luck

Sikorskyfan

[[email protected]]

It's going to be so big it will be able to double up as a regional airport:)

Dangermouse - RN SAR do have NVG.

[SARREMF]

Crabb

he said RN Merlins not 771

[[email protected]]

Ah didn't see that - but why would a RN Merlin be using a Fire Service helipad anyway?:)

[airborne_artist]

why would a RN Merlin be using a Fire Service helipad anyway?

In the world of aviation, and particularly military aviation, you have to expect the unexpected, I guess. Why go to all the trouble of building it to take a Mk3 if you can't then take a Mk1?

[mini]

Excellent thread! :ok:

[[email protected]]

AA - on that logic all the HLS should be big enough for Chinooks so we are covered for every eventuality

[RAFEmployee]

Fuselage length: 19.5 meters : 64 feet.
Length (with rotor): 22.8 meters : 74 feet 9 inches
Height (with rotor): 6.65 meters : 21 feet 10 inches
Main rotor diameter: 18.6 meters : 61 feet
Empty weight: 10,500 kilograms : 23,150 pounds

They're from memory, as you can see it's quite heavy so don't just look at dimentions, however, the Merlin can be landed just about anywhere anyway. The mountain rescue with have much more equipment on board that would add extra weight.

I feel you best bet would be to contact them and get specifications off them, aswell as speaking to the experts.

[blue monday]

Call me pedantic but huey is spelt huey not hughie as one or two people spelt it on the first page, call you self aviation enthusiasts i don't know!!!:rolleyes:

[TheWizard]

Fuselage length: 19.5 meters : 64 feet.
Length (with rotor): 22.8 meters : 74 feet 9 inches
Height (with rotor): 6.65 meters : 21 feet 10 inches
Main rotor diameter: 18.6 meters : 61 feet
Empty weight: 10,500 kilograms : 23,150 pounds

They're from memory...............


http://forums.airshows.co.uk/iB_html/non-cgi/emoticons/smilielol.gif
Do me a favour!! They are from the Aircrew Manual :8