Topic: Harrier

Just wondering, if a kit was made of a harrier. Not VTOL but just standard thrust, do you think there would be much interest?

Sounds good but I'd only be interested in a large scale kit with plenty of detail or the possibility to add your own.  I've often pondered doing one but that's as far as it ever went.  Good luck if you give it a go.

How would you duct the thrust? As per the full size through nozzles? There's a thread on here from not long ago about making a VSTOL version, but the subject of it was pretty much taken with how you transfer the thrust whether for vertical or horizontal flight. PDR is the man.

I was thinking of a model for 70 size, so small enough to transport easily.

I have a donor airframe for the basic design, the front 2 ducts would be false with the rear 2 providing forward thrust. The engine would be mounted well forward in the intake.
Its only a concept at the moment but its based on the old LMC harrier. I will take some pictures of the airframe later.

I have a bifabricated thrust tube that was bought for a Yellow phantom that looks like it might do the job.

I had a conversation with Pete (PDR) over a coffee recently about this very subject, he offered some very useful insight. IIRC the 'sit' of the aircraft was mentioned as causing a potenial problem for conventional take off and landing.

I will have a chat with him about it. I just think it would be superb to see the Harrier shape on the jet seen, One of our greatest  achievements.

I have an old jet international mag with someone who did an AV8B and Yellow aircraft mad the fuz. Its going back about 10 years or so though.

Here are a couple of pics, a new mould would have to be made.

I have an old jet international mag with someone who did an AV8B and Yellow aircraft mad the fuz. Its going back about 10 years or so though.

Would love to see that.

That looks like the old LMC kit, i used to have one of those. Bought at a club auction, bit tatty though . . . . flying was interesting at times.

Yes it is an old LMC kit, this airframe will be completely stripped and a mould taken from the fuzz. I can imagine it would be a handfull but fun.

skymaster were doing one it was on their web site don't know if it is available though

skymaster were doing one it was on their web site don't know if it is available though

I remember, it looked really promissing and then just slipped of the radar?

I remember, it looked really promissing and then just slipped of the radar?

Think there was something mentioned on RCU some months back about it still being worked on between more viable projects.

You can see it near the bottom of the news page > http://www.skymasterjet.com/news.htm

Well a lot of work has been going on with the Harrier.
The canopy area and all the nose has been completely re shaped! Loads of filler.
Its taking shape and looks superb.

Next stage is to get a thrust tube made, so the exhaust holes in the fuzz can be modified. Any one got ideas on a good manufacturer?

Once the exhaust has been modified the moulds will be done. Hope to post some pics of the progress, Plan to test fly on a Wren 70  early next year.

So Far

Is the turbine going to exit via the four thrust postions? If so, will they be vectored?

No the front two will be dummy, with the rear two providing the thrust.
I just want to get the Harrier shape flying with the turbine sound.

The fuselage will be made from lightweight epoxy cloth. Same as the Gnat I do, someone could use the kit to try and do VTOL 

Here is a comparison to the start state!

Will it be able to take off and fly with the efflux only going through the rear nozzles? Won't it put a pitch imbalance on the airframe? 

No It should be fine. There is an EDF harrier that uses the same setup. That flies superb.

Just to put to bed any thrust issues, here is a video of an EDF harrier using the rear nozzles only for thrust.

RC Jet Harrier

Same principle but bigger with the turbine music 

One of the main issues will be heat, attached is a pic of the full size solution. The same principle will be used with the shield made from heat shield matting and litho plate.

Thoughts on if its starting to look right?

I like this allot, looking good Russ though I'd want to make the GR9, what about retracts had any thought on these yet.

Thanks Lozza
The Jet 1A  noseleg looks very close to scale, the main and noseleg will be air up / spring down.
The wing tip retracts will be electric.
Main thing now is to get the thrust tube made, when the exhaust holes are modified on the plug the moulds will be made

Thoughts on if its starting to look right?

posted whilst i was repling, looks great though its going to need the pylons on, thats what made them look great low level, all that stuff hanging off the wings, what about the air intakes (small ones) will they be extras to fix on afterwards

A couple of motivation shots for you

Gr9 Harrier Around the Mach Loop Wales 2010 by lauriehughes, on Flickr


Harrier Gr9 - HDR by lauriehughes, on Flickr

The small intakes once the mould is done could be left in or cut out to suit. So many variants will make it difficult to cater for all.

Love the pics

The pylons will be a must

Loz, when are you going to stop photographing your Airfix models and airbrushing the stands out? 

Loz, when are you going to stop photographing your Airfix models and airbrushing the stands out? 

You should be on stage, drop me a PM on the quality of THE upgraded retracts for the F16 please

A couple of points:

1. Blast sheilds: On the full size these are a semi-consumable stainless steel part which wears rapidly due to both thermal effects and fatigue (crack) damage from the vibration of the exhaust blast. They are mounted on articulated brackets which allow them to change shape as they warm up. I seriously doubt that litho-plate would be rugged enough (physically or thermally) for this application in the mode, and I suspect you'd need articulated mountings to allow them to expand and change shape even on the model.

2. "Small intakes": The "Auxiliary intake doors" are just spring-loaded flaps that open when the intake (static) pressure drops more than about 5% below outside air pressure (they don't have actuators - it's the springs and air pressure that does the work). They are firly shut at all airspeeds above about 20kts because the ram-air effects inbcrease the inlet pressure. So if a model has no hover capability the doors should be in the shut position.

3. You'd need to make a choice between (as a minimum) the Harrier I varients (GR1-3, FRS1-2, FA2, AV-8A etc) and the Harrier II varients (GR5-9A, AV-8B [incl NA and II+], EAV-8B etc) when doing the mould because both wing and fuselage are very different shapes. You can make an FRS2/FA2 from an FRS1 by fitting a different nodecone and sawing through the rear fuselage to insert an extension plug (this is what was done on the upgraded aircraft, with only the new-build ones having blended shape-changes), but to convert the same basic fuselage into a Harrier II would involve so many changes as to warrant starting agaions from scratch. Similarly the wings are completely different shapes, which in turn means that the wing mounting areas of the centre fuselage are very different as well.

The plug in the above photos (very nice work, BTW - I wish I could do that sort of thing!) looks like a late FRS1, but the canopy looks a bit too GR5ish and I'm not 100% sure about the radome shape. This might be a freak of the photos, but it looks as if the nose cone is raked downwards. The GR5/7/9 nose cone does this because it only contains electronics, but the FRS1/2 nose cones were glass/kevlar radomes and were symetrical in all axes.

£0.02 supplied,

PDR

Thanks PDR, that's the sort of input I need. The nose can and will be worked on to get it as symmetrical as possible. Not sure what I can do with the canopy but i will try my best to get it looking right.
The exhaust will be done in a way that minimises the jet thrust that will hit the fuzz, having said that I will as you said look at using stainless.

The plug is being re shaped from a very early (not very scale) LMC harrier. Hence the complete overhaul of the front end.

The attached pic is the variant i would like to get close too.

Russ,
Excellent work, your Harrier is looking very nice indeed.
Next year is the 30th anniversary of the Falklands war,
it would be nice to see a turbine model flying to commemorate the Harrier's finest hour.

Will the Harrier be available to buy?

Regards Phil G.

Hi Phil
As is the Gnat, Once thorough testing has been done. Yes she will be available as a kit
I will also do the prototype in the markings of one of the Harriers that flew in the Falklands.

Ok
Need some input, the Harrier plug is now almost ready for the mould to be taken.
The secondary intakes have now been filled. Question? Would people prefer the square secondary intakes to be marked as panel lines, or completely left smooth. That way you can either cut them or leave them filled?

panel lines

Thanks Harry

If I might make a suggestion...

You could consider putting a piece of kevlar tape in the layup across the hinge area at the front of each auxilliary inlet door. Then people could simply cut around the remaining sides and use the kevlar as a sprung-closed hinge.

PDR

Good idea PDR

I will have a go on one of the fuselages. I have also just ordered an Airfix Harrier FRS.1 kit. Should show the detail such as panel lines etc

Russ