Water injection?
N4790P
Last encountered them when I did a loadsheet course for SAA around the late 80s I think. It was explained that there was big tank which would be emptied during the take off. Tank was in the wingbox area as had an open top as a closed tank would not allow the pumps to flow as fast. I seem to remember the figure of 3000kgs added if water injection was used but it was a long time ago.
Anilv
Anilv
Gentleman Aviator
Had water-meth injection on a Jet Ranger I flew in the Middle East - gosh - nearly 50 yers ago. Some days I reckon we could have used more water-meth than fuel.............
Used on most take offs in Oman.
I remember going out of Tehran in 1979, (me on jumpseat), the water ran out as we hit the inversion layer. The aircraft stopped climbing until we got a good distance from the city. The Captain wrote in the F700, (tech log), Max Continuous Thrust used for 17 mins. The answer "Noted with thanks".
There's an interesting photo of an Emerald Airways HS748 (G-ATMJ) with an engine on fire during ground runs. The rumour was that waste Avtur had been drained into a water meth drum at some time and later unknowingly decanted into the aircraft's water meth tank. 
Monarch and Dan-Air ended up with a fairly major logistical operation to make sure barrels of de-min water were properly marked and positioned at airports around the network where they were required for the performance enhancement. The marking of the barrels was much clearer after the Paninternational accident mentioned earlier, when the de-min water tanks were accidentally filled with JetA1 with dire consequences.
Hand-pumping the stuff into the aircraft was generally the F/O's job on turnround unless you could "induce" a rampie into doing it. Unless I'm much mistaken, the BA 1-11-510EDs didn't have the capability and it fell into disuse during the latter days of the type's service even on the 517FE and 518FG aircraft with Dan-Air and British World, and the ex-BCAL aircraft that ended up with European Air Charter via BA.
I do recall standing not too far behind a Tarom 1-11 operating for Adria Airways in about 1985 and getting a little bit wet as the water at the very beginning of the take-off roll was simply ejected downwards and backwards from the aircraft onto a pathway below the runway. The "extra noise" probably explains why I'm having increasingly frequent arguments nowadays with the other half about being a deaf old git...
Hand-pumping the stuff into the aircraft was generally the F/O's job on turnround unless you could "induce" a rampie into doing it. Unless I'm much mistaken, the BA 1-11-510EDs didn't have the capability and it fell into disuse during the latter days of the type's service even on the 517FE and 518FG aircraft with Dan-Air and British World, and the ex-BCAL aircraft that ended up with European Air Charter via BA.
I do recall standing not too far behind a Tarom 1-11 operating for Adria Airways in about 1985 and getting a little bit wet as the water at the very beginning of the take-off roll was simply ejected downwards and backwards from the aircraft onto a pathway below the runway. The "extra noise" probably explains why I'm having increasingly frequent arguments nowadays with the other half about being a deaf old git...
Just so the younger folk know what we are talking about, here's an AA 707 leaving LAX. It looks like they have raised the gear to clear the fence!
N4790P
Water injection flow rates on the BAC 1-11.
The water tank held 110, (1100 lbs),imp gallons and this was used up in around 2 mins. so thats around 275 lb/min per engine. The take off fuel flow would be around 10000lb/hr which is 166lb/min. Therefore the water flow was a lot higher than the fuel flow. I always though this a bit incongruous.
Smokey engines. Am I right in thinking that JP4, (Wide Cut Gasolene), caused a lot more smoke than JET-A1, (Kerosene)?
Other aircraft with water/methanol injection include the early Shorts 3-30s with the PT6A-45A and B engines and anything with the RR Dart.
How can I remember all this stuff yet don't know what day of the week it is, I put the bins out on Monday instead of Tuesday.
The water tank held 110, (1100 lbs),imp gallons and this was used up in around 2 mins. so thats around 275 lb/min per engine. The take off fuel flow would be around 10000lb/hr which is 166lb/min. Therefore the water flow was a lot higher than the fuel flow. I always though this a bit incongruous.
Smokey engines. Am I right in thinking that JP4, (Wide Cut Gasolene), caused a lot more smoke than JET-A1, (Kerosene)?
Other aircraft with water/methanol injection include the early Shorts 3-30s with the PT6A-45A and B engines and anything with the RR Dart.
How can I remember all this stuff yet don't know what day of the week it is, I put the bins out on Monday instead of Tuesday.
Flightrider
Thats correct - resulted in much fun trying to explain to various European ATC towers why we would be effectively orbiting during the departure to get to MSA before setting course!
PS How the heck has this triggered memories of all the power settings/call outs?
Unless I'm much mistaken, the BA 1-11-510EDs didn't have the capability
PS How the heck has this triggered memories of all the power settings/call outs?
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The P&W JT9D's needed a little help getting full power during hot or high Ops.
The Water Injection system had a Tank in the Dry Bay, forward of the Centre Fuel Tank. High-Capacity Electric Pumps were located in the L/H and R/H Inboard L/E Edge Area.
Tank was topped up to full with De-Min water. We had a Bowser at Heathrow specially for Demineralised Water. Probably left over from the B707's..
Water Injection was selected and armed from the F.E.'s Panel from memory and the system would run at full bore when initiated with the 3 phase Pumps activated by the Thrust Levers position, almost at T/O Power, until the Tanks were drained.
Water was introduced into the Compressor front end and would apparently increase the density of the air going through the Engine to give it a little power margin at hot or high Airfields.
The Crews we talked to said it helped a little but wasn't really that effective and was a tad unreliable.
I remember when we used to function the system after repairing it, the function would be noticeable with electrical power draw on the APU or GPU and you had to be careful with it.
Hope that helps...
And it generally ran out below 500ft..Tel Aviv we had to cross the coast above 1,000ft due to the military patrolling the beach watching out for terrorists.Of course it was rare to reach 1,000ft as we hit the inversion which put paid to a reasonable climb rate especially as we had the good old whip the flaps up at 90 seconds and reduce the power to Noise abatement setting which was below climb power.
Yes, on the Trident we only used water injection for take-off, 1st and 2nd segments so could use demineralised water, rather than water-methanol. One-Elevens could use water for Approach climb compliance so had to use methanol as anti-freeze to cope with the cold during cruise.
Yes, on the Trident we only used water injection for take-off, 1st and 2nd segments so could use demineralised water, rather than water-methanol. One-Elevens could use water for Approach climb compliance so had to use methanol as anti-freeze to cope with the cold during cruise.