Throbbing Javelin
 

In the mid-60s, I was an aircraft tradesman at Tengah and recall hearing a peculiar throbbing noise from the engine(s) of a Javelin straight after startup. I was told that this was not unusual but cannot recall what the cause was said to be (resonnance, unburnt IPN fuel from the starter system?). Can anyone please comment?

Of course, after 50 years, my memory may be playing tricks. Moreover, at the time, I was young, single and in Singapore so may have been preoccupied by throbbing of a different kind!

This seemed to be a characteristic of the A S Sapphire engine,probably intake resonance. On the web somewhere is an audio of 24 javelins doing a flypast, distinctive " Blue Note" but not like a Hunter or Meteor. Ah, nostalgia......

I thought the good looking ones batted for the same side so to speak.

I was always under the impression that the Sapphire 'Warble' was caused by the fixed Inlet guide Vanes (IGV's) at low RPM.
Sounded quite impressive on Victor 1's :)

On a quiet night in my garden in Swaffham I could clearly hear our Victor 1s taxying at Marham. As you say, a very distinctive "warble". A tad underpowered for the Victor, but I never knew a Sapphire let us down in the six years I was there.

Sapphire Warble
 

Yes,
Very distinctive during taxi and positively wierd at night. Made me think of wailing banshees for some reason ( possibly a combination of Irish blood and Guiness ).

As in, "I hope the earth really IS curved!" :ok:

CG

The Sapphire
 

Tankertrashnav, guess you were not on the early Victor 1 when we had the "centre line closure" problems with the Sapphire, not fun but resolved with the abrasive coating put inside the compressor cases to just scuff the tips of the blades to give a bit of clearance, I remember it well having to jack up the wings to get the engine doors to crutch up after many engine changes, I still have a couple of engine door bolts in the garage just to remind me what fun we had !!!!

zetec2,
centre line closure was also a feature of the same engine in the Javelin. A trick of the engine fitters at Middleton St George (33 Sqn) was to ground run the engines just when the film was starting in the cinema. The tin roof used to resonate in tune with the rumble and render the film almost inaudible.
If my understanding is correct the J35 may suffer something similar and the solution may be akin to the old method.

Throbbing Javelin
 

Jetpipe resonance.

zetec - no you are correct, by the time I made the acquaintance with the Victor the centre line closure problem had been sorted, thank goodness.

charliegolf - absolutely! Also the combined efforts of the rear crews pulling up on their seats as we approached the end of the runway used to help ;)

Javelin jet pipe resonance
 

I recall that it was caused by jet pipe resonance. I recall that there was a simple way of stopping the resonance by just increasing the idle revs slightly after start up. At Akrotiri the resonance could be heard distinctly in Limassol across the bay so it was SOP, especially at night, to keep it to a minimum. Happy Days

"Throbbing Javelin" would make a great username! :cool:

My only Javelin memories from the Tower at Tengah in 67 was the weekly incidents ... either the slipper tanks blowing off of startup, due to something to do with a starter vent being blocked, or the very agricultural u/c downlocks failing, leading to the Javelin sliding sideways off the runway.

Tower trainees were warned to expect a "Crash State One" on a weekly basis. Poor Javelins, they had had a hard life, and 64 and 60 with their Mk 9(R)s were the last in that distinguished line.

A fascinating beast - there was something about them that I simply 'liked'. I have no idea why ... perhaps it was their age?

Throbbing Javelin
 

Slight thread drift: anyone know what causes that distinctive Vulcan howl at takeoff? Didn't seem to affect all marks. The sound track to my childhood includes that eerie banshee echoing across the fields from miles away. Hearing it again as an adult instantly raised the hairs on the back of my neck.

It might interest all the responders to my original post to know something of the background to my query. I was passed some information from someone who was at Akrotiri around 1957 and thought that had seen evidence of a secret spy plane. He had been told to move away from a well-guarded part of the airfield, saw a wing shape that, years later he noticed on a B2 bomber, and heard an exhaust with a throbbing sound. He had read reports that the Aurora made a throbbing sound and now thought that he had witnessed an Aurora.

I have reported back to my correspondent that, in my view, 1957 was far too early for the hypothesised Aurora to have been flying in development, far less operationally; that the B2 wing shape is optimised for low-observable, subsonic rather than hypersonic flight; and that, if some sort of secret spy plane had been involved, it was more likely to have been a U2. I also tentatively explained the throbbing noise as possibly emanating from a Javelin, which I think were based in Cyprus at that time, as I had heard something like this while serving in the Far East.

Thank you to all those who replied to my query and confirmed that the noise I heard was indeed from a Javelin and made it likely that this was also the same sort of noise reported by my contact. I wonder if the "B2-like" wing shape that he had seen could have been on a Javelin viewed at an angle that superimposed the tail plane on the main wing and gave the appearance of a jagged rear edge.

I may have misconstrued your comment, NutLoose, so to clarify matters, the throbbing was mine! It was a phenomenon that, along with with prickly heat, us "singlies" had to endure for the whole of our tour. That's what I tell my wife, anyway.

Yes, MPN11, Javelins did slide off the runway quite often - rather elegantly as I recall - until they reached the monsoon drain! Truly a fascinating beast - big, butch, attractive in a sort of ugly way and pure British; rather like me.

Awful old photo-album scan, and I had a cheap cr*p camera too, but join me in saying the last [front line] farewell to The Dragmaster.

This posted for historic record, rather than artistry ;)

Curious that there's a dead fly in that album page that's doing a fairly good impersonation of the Markhor in the sqn badge ... how strange! :cool:

http://i319.photobucket.com/albums/m...TC/Scan_1.jpeg

Here's a couple for you MPN11 (I am sending these via an iPad, and the transfer may not be successful):


https://lh4.googleusercontent.com/bT...qg=w1912-h1230


https://lh4.googleusercontent.com/eD...rQ=w1912-h1230