Water/Methanol injection
Join Date: Mar 2004
Location: England
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I believe the original Bell206L had the capability, especially the ones used at the Grand Canyon Arizona. They had the same engine as the 206B but two extra seats, so they had WMI fitted to get the extra ooomph to get out of the landing site at Tusayan with a boatload of tourists. No idea how long it could be used for though - 30secs?
Join Date: Feb 2001
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I have flown several early model Long-Rangers with the 250 C20B engines equipped with Water Alcohol.
The tank was only 3 gallons [I think] and it was good for about 3 minutes so you had to use it wisely. It did make quite a difference in performance though.On a hot day- Instead of temping out you would Torque out.
To use you would first pull in power until the temperature was in the Yellow arc ( I don't recall the numbers), then activate the switch on the collective. The aircraft would twitch , the TOT would drop down ito the green then you could pull in the rest of the power to achieve 100 %Q. Once climbing out de-activate the system.
One time we had some Isopropyl Alcohol mixed in with the water instead of Methanol. On take-off from the base heli-pad the engine flamed out.
The tank was only 3 gallons [I think] and it was good for about 3 minutes so you had to use it wisely. It did make quite a difference in performance though.On a hot day- Instead of temping out you would Torque out.
To use you would first pull in power until the temperature was in the Yellow arc ( I don't recall the numbers), then activate the switch on the collective. The aircraft would twitch , the TOT would drop down ito the green then you could pull in the rest of the power to achieve 100 %Q. Once climbing out de-activate the system.
One time we had some Isopropyl Alcohol mixed in with the water instead of Methanol. On take-off from the base heli-pad the engine flamed out.
Join Date: Oct 2003
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We used to use it in the straight 206L models in the GOM. It wasn't required that often if you were careful, and it was only used to keep the TOT below the redline for takeoff. The tank was small, and you had to be judicious in using it during the day or you would run out. The people who ran out usually were using it to keep the TOT out of the yellow, which wasn't the correct way to do it.
I recall one unlucky pilot who had pure alcohol installed instead of the water mix. When he hit the switch, the engine really, really wound up. Overspeed, overtorque, overtemp, over everything, all in a heartbeat. He got it down safely, but it was some time before that ship flew again.
The 206L is the only model I've seen it in. Perhaps there are others, but it's only needed in a very underpowered helicopter, which the straight L was. It did very well in cruise, but you had to be really careful on the takeoff and landing.
I recall one unlucky pilot who had pure alcohol installed instead of the water mix. When he hit the switch, the engine really, really wound up. Overspeed, overtorque, overtemp, over everything, all in a heartbeat. He got it down safely, but it was some time before that ship flew again.
The 206L is the only model I've seen it in. Perhaps there are others, but it's only needed in a very underpowered helicopter, which the straight L was. It did very well in cruise, but you had to be really careful on the takeoff and landing.
Join Date: Jul 2002
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Did the same in a straight 206L. I seem to recall that if you added the water before the TOT climbed high enough, you stood the chance of flaming out. I can't remember if that was in the flight manual or if it was a wives tale from someone. It was fun to use and get a kick in the seat of your pants when it hit though.
Join Date: Jan 2004
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From 206L-FMS1
WATER-ALCOHOL INJECTION PROCEDURE
NOTE
The available injection time is approximately
three (3) minutes, depending upon the flow
rate. When the tank quantity is depleted to
approximately one-half (l/2) gallon the W/A
LOW LEVEL (amber) light will illuminate.
WATER-ALCOHOL switch - ON.
Turbine outlet temperature (TOT) - Minimum 738°C.
W/A INJECT switch (collective stick ) - ON.
GREEN FLOW LIGHT - ON (Failure of light to illuminate
indicates no flow.)
Monitor TOT, N1, and torque instruments. Adjust power as
required to maintain engine operation within operating
limits.
When the W/A LOW LEVEL amber light
illuminates, the remaining fluid will provide
approximately 30 seconds of water-alcohol
injection time.
W/A LOW LEVEL amber light - When light illuminates,
schedule the use of the remaining fluid and be prepared to
reduce power to prevent exceeding the limit.
If water-alcohol is depleted during system
operation, a torsional oscillation will be
evident, reduce power as necessary to prevent
TOT from exceeding 810°C turn system off.
Prior to terminating water-alcohol injection flow, reduce
power and TOT.
W/A INJECT switch - OFF, adjust power and TOT as
required.
WATER-ALCOHOL switch - OFF.
NOTE
The available injection time is approximately
three (3) minutes, depending upon the flow
rate. When the tank quantity is depleted to
approximately one-half (l/2) gallon the W/A
LOW LEVEL (amber) light will illuminate.
WATER-ALCOHOL switch - ON.
Turbine outlet temperature (TOT) - Minimum 738°C.
W/A INJECT switch (collective stick ) - ON.
GREEN FLOW LIGHT - ON (Failure of light to illuminate
indicates no flow.)
Monitor TOT, N1, and torque instruments. Adjust power as
required to maintain engine operation within operating
limits.
When the W/A LOW LEVEL amber light
illuminates, the remaining fluid will provide
approximately 30 seconds of water-alcohol
injection time.
W/A LOW LEVEL amber light - When light illuminates,
schedule the use of the remaining fluid and be prepared to
reduce power to prevent exceeding the limit.
If water-alcohol is depleted during system
operation, a torsional oscillation will be
evident, reduce power as necessary to prevent
TOT from exceeding 810°C turn system off.
Prior to terminating water-alcohol injection flow, reduce
power and TOT.
W/A INJECT switch - OFF, adjust power and TOT as
required.
WATER-ALCOHOL switch - OFF.
A wonderful Bell approach to curing problems of too little power....reckon EC is next?
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W/A was short term solution
W/A was stop-gap measure till C28 powered L1 came along.
Early B & L had very heavy Pan-style emergency floats with steel bottles in baggabe compartment that weighed 100-150 pounds more than todays light weight systems.
Interesting side effect of W/A was coke build up on power turbine which could delay the main rotor turning on start-up. When it did break loose spin up was a real thrill.
Many early L models have been converted to C20R engines with 450SHP. I am told that they are sweet aircraft now mainly operating in Canada.
Early B & L had very heavy Pan-style emergency floats with steel bottles in baggabe compartment that weighed 100-150 pounds more than todays light weight systems.
Interesting side effect of W/A was coke build up on power turbine which could delay the main rotor turning on start-up. When it did break loose spin up was a real thrill.
Many early L models have been converted to C20R engines with 450SHP. I am told that they are sweet aircraft now mainly operating in Canada.
Senis Semper Fidelis
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Seem to remember the RR Merlin and Griffon also had this sort of water/methanol injection thingy, fitted to the rear part of the main supercharger outlet(to inlet manifold), old timer told me it made em go faster by producing more grunt.
Funny that, I just tried lighting some H20, it didn't burn!
Vfr
Funny that, I just tried lighting some H20, it didn't burn!
Vfr
Join Date: Feb 2001
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VFR PILOT : It works along the lines of leaning the mixture in a piston engine.
The introduction of the Water Meth (WM) replaces some of the fuel voulume there by leaning the mixture but without the detrimental effect that a lean mixture has on cylinder head temperatures.
The mixture is leaner because the Fuel air ratio is reduced but the volume is the same, comprised of a WM/fuel mixture.
The introduction of the Water Meth (WM) replaces some of the fuel voulume there by leaning the mixture but without the detrimental effect that a lean mixture has on cylinder head temperatures.
The mixture is leaner because the Fuel air ratio is reduced but the volume is the same, comprised of a WM/fuel mixture.
Six of my 8 206 hours were on the early (-A ?) models in Oman in the 1980s. They certainly needed the water/meth to lift anything much more than the proverbial half-a-verbal-message.
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I seem to remember flying a 206 L on the British register with the injection kit fitted in the boot some years back. G-GLDN or something similar not sure if it is still around or got the kit fitted.
Join Date: May 1999
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The pink LongRanger had water / meth, and it worked very well. Used it mostly coming out of Hayman Island's tight'ish pad in summer full of Japanese and American tourists.
The only gotcha was to remember to lower the collective (after translation) BEFORE switching off the water/meth!
That pink LongRanger? Painted in the same colors of a then (still?) flamboyant hairdresser in Brisbane. Matched his Cigarette class offshore racing boat. Must have been a sponsorship deal I guess. The Japanese tourists LOVED it. They all wanted to be photographed in front of it. My, that's going back hey Gazz…
P.s. The 206 on floats had hydraulic tail rotor pedals...that was good sport on occasions!
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hmm, VH-HJL ?? from memory?
If I recall, Helijet replaced the water / meth C20B with a C20R the engine that was going to save the world in hot and / or high ops. It was hopeless, was little better than the C20B. About the same time Pacific ordered 20 ? or so H500's with the R engines to use in New Guinea, got the first one and cancelled the order. If you didn’t have 17%n1, don’t open the throttle. Helijet ended up placing two batteries in the longranger to help it start. Didn’t work, the R was always a lemon.
If I recall, Helijet replaced the water / meth C20B with a C20R the engine that was going to save the world in hot and / or high ops. It was hopeless, was little better than the C20B. About the same time Pacific ordered 20 ? or so H500's with the R engines to use in New Guinea, got the first one and cancelled the order. If you didn’t have 17%n1, don’t open the throttle. Helijet ended up placing two batteries in the longranger to help it start. Didn’t work, the R was always a lemon.
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IHL,
the water injection does lean out the mixture, but that is not why it adds power (in fact, that effect robs a little of the power gain it creates). This is true in either case, piston or turbine. For turbocharged piston engines, the cooling prevents detonation, primarily, allowing the high boost pressures, but it is the cooling that makes the injection work.
The water injection works because it cools off the inlet air to the pistons or compressor, mostly due to the evaporation of the water.
The effect of cooling off the air is strong, an engine gains power by about 1% for each degree C that we cool the inlet air.
Alcohol is added to the water so that it does not freeze, and has little effect on the general purpose of the spray (it does burn, so it has a bit of fuel effect, and on pistons it does increase the octane of the mix, and so helps prevent detonation in addition to the cooling effect).
the water injection does lean out the mixture, but that is not why it adds power (in fact, that effect robs a little of the power gain it creates). This is true in either case, piston or turbine. For turbocharged piston engines, the cooling prevents detonation, primarily, allowing the high boost pressures, but it is the cooling that makes the injection work.
The water injection works because it cools off the inlet air to the pistons or compressor, mostly due to the evaporation of the water.
The effect of cooling off the air is strong, an engine gains power by about 1% for each degree C that we cool the inlet air.
Alcohol is added to the water so that it does not freeze, and has little effect on the general purpose of the spray (it does burn, so it has a bit of fuel effect, and on pistons it does increase the octane of the mix, and so helps prevent detonation in addition to the cooling effect).
Last edited by NickLappos; 16th Mar 2005 at 10:26.