Thank you John.

I apologise for the delay in acknowledging your input - a short but warm break in the ME kept me away from the internet.

It does make more sense now. I will try different CIs during the flight preparation phase to see what sort of 'scatter' I get which might help to explain further.

Again, many thanks to you and your pal for the time and effort.

mcdhu

PS Just finished Tony Blackmaman's 'Vulcan Test Pilot' - an interesting read.

Hi All
I have just finished the book and think it is excellent and will recommend it to anyone.
In the book John says that the last time he flew a Harrier at Farnborough was in 1992, when he displayed an Indian Navy example. Hear is one of my pictures from that show.

http://i101.photobucket.com/albums/m...Seaharrier.jpg


The one think about the book that puzzled me was that I bought it from my local Smiths in Sale, Cheshire and it was SIGNED?! I have visions of poor John sitting in his front room, surrounded by mountains of the things, signing every one!
Thanks any way.

Rgds Dr I

Dr Illitout

Thank you.

But it was Farnborough 1982 not 1992.

Time flies

JF

Bought John's latest Book last month, at a book signing at White Waltham.

I will treasure it!!


And yes he did sign it!!

I will be ordering my copy when I am next back in the UK!

Looks like it is a fascinating read, so thank you John!

It is a fascinating read. I've been reading and re-reading the section in elevator vs. throttle for speed/flight path control on final for GA aircraft.

Thought-provoking stuff, and a very good time for me to be thinking about this (as neither technique is - as yet - "hard wired" in what passes for my brain).

Great book, John. Many thanks.

FRS51 Display
 

John,

Wasn't that the time ( my Father was crew-chief ) when you levelled out a little early from your unique climb, carried on the rest of the display then landed with a grin, " Always wondered what would happen if I lost the water at that point ! " ( the pump which does very high rev's had exploded ).

DZ

DZ

It may have been - I recall the water pump event but not which particular aircraft was involved.

But if your Dad says so....

JF

Water pump at Farnborough
 

Hello John,

For the sake of accuracy for readers here, I suspect you were being polite about ' not recalling which aircraft ' the pump failed on; Dad now thinks it was G-VTOL, while I've always been sure it was the FRS51 he related the tale about...

Either way, seeing the water pump light go out / red whatever it did, and feel a loss of a bit of power, was probably not what you'd have wished for at that moment !

The pump was replaced ( into a Harrier of some form, at least that's pretty certain ) and the aircraft fine for the next day, quite an ad' for the aircraft really, let alone pilot, but I doubt the happening was exactly broadcast.

Apologies for any confusion to others.

DZ

Double Zero

Your dad is right it was G-VTOL.

The light was green when water was flowing and out when it was not.

No great drama but if the light went out the JPT would rise pretty quickly if you did not throttle back somewhat.

JF

John,

Thanks for that. No problem, with my years of BAe training I'll simply not tell Dad he was right and I was wrong.

Regards,

DZ

Harrier Question
 

John, I wonder if you could humour my curiosity with this question !



Why is the throttle lever placed outboard of the nozzle control lever
It seems counterintuitive, to my thinking a Pilot would want the throttle lever to be closer to hand and not have to 'reach around' the nozzle lever ?


I am sure there is a good reason. Thanks for a great read by the way, enjoyed your book very much.

stilton

Well what an interesting question. I have no idea why they are like they are and the two pilots who (probably) discussed the options with the designers in 1959 are both dead. I tried to contact Ralph Hooper but could not reach him. When I do I will let you know. Certainly I know Bill and Hugh did NOT want the sense of the nozzle lever to be aligned with the nozzles (ie nozzle lever aft when nozzles aft and nozzle lever forward when nozzles forward). This was because people are used to pushing things forward to go faster (whether it be RPM or airspeed)

I suspect (not the same thing as know) that the position of the throttle was chosen to be like any fighter which is usually fairly well outboard and where your left hand naturally falls - rather than close to your body. Remember that the throttle traditionally carries quite a few ancilliary controls including a twist grip (in those day) for gunsight ranging (youngsters will not know of wot I speak) and I would not like to operate that close to my thigh.

If my suspicions are correct then the only place left for the small and simple nozzle lever was inboard. Speaking personally I have never felt I wanted them round the other way.

Glad you enjoyed the book.

JF


PS I have just managed to raise Ralph and he has no recollection of any discussions on your topic only the one I mentioned above regarding the sense of the lever.

He did say that IF anybody had wanted them the other way round he would have worried that more lateral space would have been taken up and that was at a premium.

JF

throttle and nozzle
 

As someone paid (on occasion) to cogitate on matters pertaining to the control of STOVL aircraft, I'd like to add to John's reply. It's my opinion that from the outset of the P1127 the designers had in mind that firstly they were in the warplane business and secondly that to make a VTOL (as it began) one they should depart from established sound warplane practice to the minimum extent practicable. So as John says, the throttle lever followed established practice of being a chunky bit of kit that fell easily to hand and had room for various important switches. Various other reasons (not least doing things in a manner perceived to be above all reliable given current proven technology) resulted in the nozzles being controlled by a mechanical lever. An electrical switch could go on the throttle lever (and later on of course it did in the nozzle-nudge system) or, as with the Yak-38, on the stick-top (although it has a mechanical conventional-flight/powered-lift selector inboard of the throttle too), but a mechanical lever had to realistically go elsewhere. The nozzle lever had to go close to the throttle, because at several stages of flight right after making a significant input with one there is a need to make one or more inputs with the other. It would also clearly help if the two levers were radically different in feel, to reduce (but alas, as history has shown, not eliminate) the odds of moving the wrong one. So big throttle meant smaller nozzle lever. A small nozzle lever outboard of the throttle would be awkward, as would any lever not big enough to stand well above the throttle. So as the smaller lever, the nozzle lever had to go inboard.

It's worth also pointing out that there's a handy little shelf outboard of the throttle where some some hydraulic pressure gauges live. In the hover this shelf is well placed as a hand-rest, allowing subtle movements of the throttle lever (try using your computer's mouse without resting your hand on the desk/mouse-mat - doable but not easy to be precise). If I dig around at work (fall-out from office moves permitting) I may be able to find out when this shelf was added. If it was there from the outset then it would also have influenced the original choice of lever arrangement. An outboard nozzle lever would be tucked away under this shelf, or have to be on top of it somehow. As John says, the Harrier (less so Harrier II) cockpits are rather cosy, so I doubt an ergonomic solution with the levers swapped over would fit.

F-35B has a really chunky throttle grip (so chunky we had to have a bit cut off to fit it in a Harrier cockpit). It has no nozzle lever at all.

Thank you for your replys John and ' Hoverstop' that certainly clears things up for me.


Was there ever any consideration of not having a nozzle lever at all, but simply a switch on top of the throttle rather like a pitch trim switch ?


I think you mention in your book that the Sea Harrier had such a device for moving the nozzles within a limited range.

NoHoverstop and stilton

Given that Ralph designed the P1127 and that he has no recollection of any discussions re the juxtaposition of the two controls I think we can take it that it just happened the way it did 'cos it seemed the easy/natural solution at the time.

Talk of the outboard shelf does remind me that it was deliberately added as a hand steady (Hugh deffo told me that) and that once it existed it was seen that the Hyd gauges would go in nicely - efficient use of space thing again.

As to whether it would have been nice to operate the nozzles from the top of the stick I can only say "not 'alf" whenever they were moved as a flying control (ie accel transition and the end of the decel transition and at the hover). However when used as a selection device (ie putting them to the hoverstop before a VTO or down for an STO or raising them after a landing) then a lever was clearly quicker and easier to use.

Indeed after the hole in the wood night trials in 1966 I started a campaign that led to the nudger on the throttle (I would have been happy with the sticktop but the throttle had the airbrake control which was redundant in the circuit so could become dual use). In the P1127 days I don't think the use of an electric switch for the full authority control of the nozzles would have been tolerated on safety grounds. I only got the nudger through because it was fine limited to plus/minus 10 deg.

Jumping on to the VAAC I preferred the speed inceptor to be on the stick (the so called 1 1/2 inceptor layout) meaning you used your right hand for everything associated with flying the aircraft which gave me a sense of very low workload. (as the docs told me when I said this "ah Farley you were only using the left hand side of the brain with nothing for the right hand side to do - that will seem a doddle")

Sorry - you got me going again. Sad really.

JF

Nozzle control
 

Hello John & all,

Just for info', I expect you probably tried it John, but in the late 80's I photographed a 'future projects' cockpit ( maybe with JSF or P1216 in mind, probably just an experiment ) which had the nozzles controlled by twisting the throttle.

With a significant nozzle angle display on the HUD !

I thought it looked as if one might easily inadvertently twist the lever when moving it fore & aft, though the technician ' flying ' it seemed to get on ok.

As history shows, it seems to have been surpassed anyway.

DZ

Very interesting, thank you for your reply John.

The book has just landed on my desk
 

:ok:

Thank you John for what looks like a fantastic read and to Flyer for an excellent service.

Have just read chapter one, marvelous :D

I am now about to bunk off work and settle down with it for the afternoon ;)

Stilton

Had another chat with Ralph Hooper earlier this week. He remarked that while he had remembered nothing that made him think other than the lever just happened to be put inside the throttle (on the basis that there was nothing to make one put it outside) he said if you were looking for a reason today then how about "Throttles are instinctive things but setting the nozzle angle needed a scale alongside the lever and that would be easier to read on the inside"

http://img.photobucket.com/albums/v1...leverP1127.jpg