Smoke from a Hawk

[Heli32]

Can someone tell me how the display smoke system works on a Red Arrows Hawk. Any info much appreciated.

[gashman]

isn't it diesel sprayed into the hot gasses from the exhaust, which then vapuorises? Different dye added to the mix gives diffent coulours. I think that's how the aerobatic prop dudes do it too.

[Navaleye]

IIRC, the "white" smoke diesel has no dye at all.

[movadinkampa747]

Yes the pilot switches it on.

[Megaton]

Commercially available dye mixed with diesel in varying quantities depending on the event. For trg, weak mixture used with full strength for special occasions.

http://www.rohmhaas.com/markers/automates.html

[The Helpful Stacker]

According to Mr Marios Matsakis (MP) it causes Leukaemia.:rolleyes:

[Talking Radalt]

Commercially available dye mixed with diesel in varying quantities depending on the event. For trg, weak mixture used with full strength for special occasions.


Bit like the beer in the NAAFI bop then? :O

[The Helpful Stacker]

Hey, NAFFI beer doesn't have a thing on Keo brandy.

The bottle says aged 5 years, I think they mixed years up with minutes....

[akula]

Dye Team
It’s not only the formation aerobatic displays in the air that draw crowds to watch The Red Arrows. Whenever the aircraft land at a public airfield, an audience always gathers to watch the hard-working members of the Blues carrying out a multitude of servicing tasks to ensure that the aircraft are fully prepared for the next display.

One of the most common questions that the Red Arrows’ Support Team are asked is “Who are the men wearing the silver suits?” The answer to the mystery is that they are members of the ‘Dye Team’, with the weighty (and messy!) responsibility of replenishing the diesel and dye used to create the Red Arrows’ famous ‘smoke’.

The vapour trails (often known as the ‘smoke’) are a crucial element of Red Arrows’ displays. The primary reason that the Team use smoke is that of flight safety. The vapour trails allow Red 1 to judge the wind speed and wind direction far more accurately than by any other means. Also, due to its size and shape, the Hawk aircraft is not the easiest aircraft to spot in the sky. The smoke allows both Red 1 and the Synchro Leader to keep sight of each other in the second half of the show when Enid, Gypo and the Synchro Pair are frequently several miles apart. The vivid and colourful smoke trails also add a huge amount to the impact of the display when viewed from the ground. Manoeuvres such as the Heart, the Champagne Split and the Gypo Break would not be the same without dramatic smoke trails filling the sky.

The basic smoke colour is white, and is produced by injecting diesel into the hot exhaust from the jet engine. This reaches extremely high temperatures of over 400 degrees centigrade, vaporizing immediately. The blue and red colours are made by mixing dye with the diesel. The dye and diesel is stored in a specially-modified centreline pod fitted to each of the aircraft. The pilot releases the liquid by pushing one of three buttons on the control column. During the display each aircraft can produce smoke for a maximum duration of 7 minutes. This gives the pilot 5 minutes of white smoke, and 1 minute each of red and blue smoke. For this reason, a ‘smoke plot’ is worked out extremely carefully during winter training by the Team’s Executive Officer, to ensure that no aircraft runs out of smoke before the end of the display. During the winter, the Dye Team provide valuable feedback to the pilots, informing them of the amounts of spare diesel left in each aircraft after every training sortie.

For all of the reasons outlined above, the role of the Dye Team is an important one. There are four members of the Team lead by Corporal Craig Lynch. They are supplemented by other members of the Blues, who rotate through the team in order to learn more about the tasks they perform.

Replenishing the diesel which creates the white smoke and the diesel/dye mixture which creates the coloured smoke is done in two separate operations. First, the pressure which has built up in the centerline pod is released. Then, diesel is fed into the correct valve at the front of the centreline pod from a diesel bowser. There are no level indicators to show when the diesel section of the pod is full – an engineer is stationed at the rear of the pod to watch carefully for tell-tale white vapour emitting from the vent pipe. Once the vapour is spotted, the call of “It’s Gone” is given and the technician in charge of the feeder pipe connected to the front of the pod turns the diesel supply off and shouts “White’s Off”.

Replenishing the coloured dye/diesel mix takes a team of three people. This stage of the procedure is supervised particularly carefully – imagine the embarrassment that would be caused if the wrong colours were put in the wrong sections of the pod! Purple smoke! The most crucial piece of equipment to the Team’s work is the Dye Rig, which contains the dye/diesel mixture. Every display uses up one barrel of red dye and one of blue dye, which are then topped up with diesel. The Dye Team are very protective of their Dye Rig, and to hear them talk about it, you would think it was almost human! Indeed, each year it is christened after the Dye Team Leader; in previous years it has been called ‘Harriet’ and ‘Norma’ after Corporal Harry Harrison and Corporal Norm Gage.

The Team always fill the two colours in the same order to prevent confusion; red then blue. One engineer operates the flow buttons on the dye rig, one connects the pipe to the valve at the front of the pod and one checks for the level at the rear of the pod. The call goes out “Red On”, followed by “Pumping Red”, at which point the Dye Rig operator presses the button to start the replenishment process. Again, there is no dial or gauge to show when the pod is full, and so the engineers have developed their own method of ensuring that the coloured liquid does not overflow and cause a horrible mess. You can generally spot which of the Team have been assigned the job of checking the dye mixture level – by their multi-coloured ears! The only way to tell how full the pod is to press your ear up against the back of the pod to hear when the valve begins to quietly ‘chatter’ – no easy feat on a noisy airfield. Again, the urgent call of “It’s gone” is followed by “Red Off” from both the Dye Rig operator and the pipe connector. The whole process is then repeated for the blue mixture.

As you can imagine, the job of replenishing the dye and diesel can be a messy one! The dye is not easily removed if it stains skin and clothing, and despite the care taken by the Team, dye sometimes escapes! In order to protect the engineers against being multi-coloured for the whole of the summer, the Team wear special protective silver overalls, thick gloves and goggles. Because of their protective qualities, the suits get extremely warm – the engineers describe it as a ‘personal sauna’! So next time you watch men dressed in strange silver servicing the aircraft on a hot summer’s day, spare a thought for the hardworking and intrepid Red Arrows 2004 Dye Team.



ALWAYS assume NEVER check

[seand]

When British Aerospace were testing the smoke system at Dunsfold to get the corrent colour, a number of Cars ended up with a new paint job, can't remember whether it was the arrows hawk or overseas.:)

[airborne_artist]

Can confirm that the dye is impossible to wash out; The Reds stopped overnight at Leeming in spring of 79. The more senior course on RN EFTS thought it would be a jolly jape to zap the a/c with Fly Navy stickers. Gnats duly zapped, the RN lads then waited by the pan for the Reds to taxi out, to give them a cheery wave.

Cue at least one Red who took aim with the stern of the Gnat, and hit the red smoke - how we laughed :E :E

[Megaton]

IIRC I think some of the pilots' cars got inadvertantly smoked a few years ago by the engineers who were diagnosing a problem with the smoke system with the donk running. Oh my, how they must have laughed when their motors were given a respray.

[peterperfect]

Interesting facts number 12,324b(i) para 2:

John Noakes, ex Blue Peter, ex Shep the dog etc, used to replenish the then Gnatted Sparrow's dye tanks in the 60s when he was a baby engine fitter in the RAF !!

[scottyhs]

On discovery wings they did a great explanation of all things red arrows including the smoke system which i believe is a 3 chambered pod underneath with diesel which vaporises and causes the smoke! Erm ill have a look see if ive got it on Sky+ if not maybe you could contact them and ask??

[Megaton]

To be pedantic, I believe the diesel and dye mixture sublimates rather than vapourises!

[scottyhs]

lol i apologise

[Farmer 1]

Who mentioned pedantic?

sublima'tion noun the change from solid to vapour without passing through the liquid state, usually with subsequent change back to solid (chemistry); purification by this process; a sublimate; elevation; ecstasy; the acme, height; transmutation into something higher; the unconscious diversion towards higher aims or more socially acceptable actions of the energy derived from an instinct which is denied gratification, such as an aggressive or sexual impulse.
The Chambers Dictionary. Copyright © 1994 by Chambers Harrap Publishers, Ltd. All rights reserved.


I would highlight the appropriate definition, if only I could decide which was the correct one.

However, unless the stuff is frozen, I think you'll find it (the diesel/dye mixture, that is) vaporises.

[Megaton]

Stand corrected. You are correct. Never check, always assume. :)

[scottyhs]

in that case i dont apologise in the words of monty python "i fart in your general direction" mwahahaha

[x10ge]

Going back 36 years the 'stuff' could be removed from carpets clothes, hands and the aeroplane using meths. I don't know if the current dye is the same but I guess it is.

[Heli32]

Thanks for all your help with this. Anyone got any pictures showing the delivery nozzles at the jet pipe, the tank and the control column selectors?