EH101 / HMA.1 Engine photos

[Phoinix]

I'm building a model Merlin helo, and some details are missing. Going along with building it, i've been learning a lot, but not enough. I need some help from guys who have been in actual contact with the beast.

Are there any photos available capturing some glimps of the engine compartment? I've been searching the web, and no resoults. If not, any GE CT7-6 than?

How are the engines numbered? From left to right 1-3 or is the central engine nr. 3?

I' ve been wondering about these "intake" holes labeled "Fire Access" What are they for? Is that chrome stick inside a grip handle or something? These are located on every engine, on the side and on the top side.



While you are at it, what are these "another exhaust tubes" linked to the main chimney?

[Impress to inflate]

I've been flying with one of the pre-production test pilots on the 101 project. He tells me that the engines are numbered 1 on the left hand side, three in the centre and two on the right hand side. The engines shown are Rolls Royce RTMs and not CT 7s . Will you put on the pics of your model when you have finished it ITI

[Phoinix]

Sorry, my bad on the engines. GE's are probalby for US market, right? Thank you for the info ITI.
Here are a few in-progress shots:







Wilco, pics will be displayed when finished.

[Lunar]

Just like the way Westland build the real thing!

Lunar

[sprocket]

I' ve been wondering about these "intake" holes labeled "Fire Access" What are they for?

My 2 cents worth: Usually for fire extinguisher access (hand held) if cowls are closed.

Here is a link to EH 101/102 seating arrangements (as provided by Gooooooogle) ...

http://www.hku.hk/csuhp/roomgal_eh.htm

[Phoinix]

Good one! Didn't know they nade 102 as well.

[dangermouse]

correct info

Ther are ome people that tell enormous porkies on this site..

Impress. I would love to know which TP you flew with, the initials will do, as I actually to happen to know most of the 101 TPs and the info you quoted is completely wrong (actually I think you made it up)

Phoenix, very nice job, is that the Italeri or Revell kit?

Here are the answers

Engines are numbered left to right, 1 (port) , 2 (middle) and 3 (stbd)

The apertures on the cowlings are auxiliary fire extinguisher holes and act a cooling air intakes for the engine bay eductors. The silver rod is the support strut that supports the cowlings when open, it is only on the side openings on no1 and 3

The other exhaust is the outlet for the inlet particle seperator and is always on the port side of the engine

here is a link to the Rolls Royce site that has pics of the RTM322 as fitted to the Merlin

http://www.rolls-royce.com/defence_a...22/default.jsp

I look fwd to seeing the completed model


DM

[Phoinix]

It's Italeri, but in general, kits are the same, same mould.

Thank you for the info. Italeri sure got it wrong with the "other exhaust", always pointing away from the fuselage.

Thank you again! I'll have to make some corrections i guess.

[Graviman]

Good site DangerMouse. That's 1735 kW for 244.5 kg or 7.1kW/kg - i'm just keeping tally for my own comparative purposes (helicopter engine feasibility study).

The power is maximum take-off power? What else is needed in the weight for installation into an actual helicopter? Is there any way of obtaining more engineering data? I'm specifically thinking BSFC (Brake Specific Fuel Consumption) and engine efficiency maps.

Great model Phoinix! I have a Concorde still in it's box (I'm quite a fan) - maybe i should learn a trick or two from you first. BTW what purpose does the fairing above the pilots serve? Is this part of the system to remove particulates from engine ingestion?

Mart

[Phoinix]

Thank you Graviman. Building plastic models is easy, as long as you pay attention to little details. Condcorde is a beautiful bird, don't keep it in a box, show it off. That thing above the pilots is the sun screen



It's actualy there

I was comparing the different versions of 101, and i have come accross a question. Why does the UK merlin have single wheel on the main landing gear, italian navy has a pair, others also. What's the story behind that?

[widgeon]

Sprocket is the overhead projector in the picture you provided link to for the pre flight briefing ?. I saw the fuselage mockup for the Wg34 in Yeovil around 1979 , it has grown quite a bit since then.

[Ian Corrigible]

Originally Posted by Phoinix

How are the engines numbered? From left to right 1-3 or is the central engine nr. 3?

As Dangermouse states the donks are numbered L-R.

Originally Posted by Graviman

That's 1735 kW for 244.5 kg or 7.1kW/kg - i'm just keeping tally for my own comparative purposes (helicopter engine feasibility study)

The RN’s HM Mk1 uses the RTM322-01/1, rated at 1669 kW T/O and 1518 kW max continuous. The RAF HC Mk3 and export EH101s use the –01/8 or Mk250 (1694/1407 kW). Italian Navy aircraft use the T700/T6A (1491/1327 kW), while Canadian CH-149s use the T700/T6A1 (1626/1394kW). The USMC’s VH-71A increment 1 will use the CT7-8E (1864/1522 kW), while the most powerful version of the entire EH101/Merlin family will be the follow-on VH-71B Increment 2, powered by the CT7-8C (2291/1825 kW).

Originally Posted by Graviman

BTW what purpose does the fairing above the pilots serve? Is this part of the system to remove particulates from engine ingestion?

The fairing contains a number of sub-systems, including collective actuators, the rotor ice protection unit, hydraulic connectors, rotor brake & actuator, IHPS aux reservoirs, etc. The engine IPS are relatively small components attached directly to the front of the engine compressor (some other birds, such as the NH90, use an aircraft-mounted separator).

Originally Posted by Phoinix

Thank you for the info. Italeri sure got it wrong with the "other exhaust", always pointing away from the fuselage.

The exhaust does always point away from the fuselage (decent shot of a Marina Italiana EH101 here). The point made by Dangermouse is that the IPS duct always rejoins the engine exhaust on the LHS.

I/C

[Phoinix]

I ment that second exhaust... from particle separator. I know it is pointed away from the airframe

[Graviman]

Thanks for the engine and fairing info, Iain. I meant to ask was the fairing shape an aerodynamic feature helping with particle seperation. I guess they must have done a lot of wind tunnel time to find a shape to package the various actuators, connectors, reservoirs etc. Just looks like the idea was to have relatively laminar flow past the engine intakes in forward flight.

Mart

[Impress to inflate]

Dangermouse, the person I am flying with was one of the civil TP's payed for by Westland in the 90's when the 101s had the underpowered CT7s. He recalls that the engines were numbered in the Tristar style as I mentioned. Your initials arent TN are they ? The civie test flights were done in Southern Italy from 96 onward. Hope this answers your problems in life. No deliberate porkies have been posted by me, as I have just said "He recalls".

[212man]

I think you will find they were BHL line pilots (plus TREs), not TPs.

I can hardly imagine TN asking this question (earlier thread):

What defines how many pilots a Civilian helicopter needs? Why can a military variant of an aircraft fly with 1 pilot yet the civil aircraft needs 2?

is it a size thing?

any advice from JAR?FAR?BCAR would help

thanx

DM

[dangermouse]

OK

OK impress, point made and taken, his recall was incorrect

My initials are not TN

As for single wheels, the deck handling system on the Type 23 frigate will not work with a twin wheel undercarriage and the Merlin Mk1 doesnt need to land on soft ground (according to the specification).

The only other aircraft with single wheels is the first Japanese aircraft used by the Tokyo police.

FAA/CAA/JAA rules mandated that the 101 be flown twin pilot, as it is certified as a passenger carrying aircraft to BCAR section G, FAA29 etc.

The RAF crew the front with 2, only one needs to be a pilot however. The RN use 1 due to the requirement to have minimum crew on a ship. Actually the front end has a different layout than other variant to ccount for that.

DM

[Ian Corrigible]

Originally Posted by dangermouse

The only other aircraft with single wheels is the first Japanese aircraft used by the Tokyo police

...and the best-selling Heliliner...

I/C

[The Ferret]

Merlin Single Wheels

Dangermouse - you are quite correct that single wheels will only work with the frigate deck handling system but that is not the reason that the Merlin HM Mk 1 has single wheels. Once upon a time the Merlin Mk 1 design included twin wheels - if you think about the redundancy, safety issues and ability to land on weaker surfaces (with the current Merlin max weight it is currently very limited where it can land and taxi - and I mean at airports too!) it would make sense to have twin wheels would it not? Then somewhere in the procurement process the MOD were looking to make some savings measures as they apparently ran out of cash one year - so they opted to save some money by only fitting single main wheels - then they designed the deck handling system around that design and now it's much too expensive to revert to the safer and more operationally desireable twin wheels as the handling system would need to be completely redesigned! This is very typical of most MOD projects!

The Ferret

[dangermouse]

absolute b******s !!!!!

Yeovil calling

I have been involved with the aircraft for over 15 years and yet the BS piles higher and higher

The spec for the aircraft ALWAYS had a single wheel requirement, saving costs had nothing to do with it. The ship deck handling system was frozen before a twin wheel system was ever flown and all the prototype aircraft had single wheels. The decision was taken at productionisation to change the undercarriage installation to allow a twin wheel to be fitted if other cutomers required it, and as I said previously the aircraft meets the RN specification. Intersetingly it is not the main wheels that would be the problem but the nosewheels which are different between single/twin U/C.

The only additional limit that a single wheel places on the aircraft is not to operate on very soft ground (CBR<5) which frnakly for a shipborne ASW aircraft is hardly a problem, all other ground limits are common (including operating at 60 kts at max weight) between undercarriage systems. With regards to airfield operations the Mk1 is no more limited than a Tornado or Typhoon (work out the ground loading per tyre) so your statement bout limited ares of operation is strange.

There are obvious cost and weight savings associated with a single wheel main undercarriage that cannot be ignored but to say that the driver was just cost is patently untrue. Why fit something you can do without (WHL would have been taken to the cleaners for trying that one on!). Actually putting a single wheel on the Mk1 would tend to increase costs in any case as the oleo characteristics, nose gear, wheels and hubs are now unique among all military variants.

Ian C, in my response I ignored the development aircraft as the undercarriage system on those cannot take a twin wheel anyway, and the Heliliner was PP8 (yes I know WHL are still waiting for the launch order but I suppose the VH71 is close to the same job !!).

looking fwd to putting more myths to bed.....

DM