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There are a couple of stories that pertain to the Ft.Huachuca posting above.One now,and one later.Back in 1983,there were two runways at FHU,both of which were relatively short.I checked the back of one of the photos and it was dated as June 4,1983 as the day that we worked the fire near Mexico.
That was the first time that I'd flown a tanker out of Ft.Huachuca,but I'd been there a few times in a Twin Beech.We hauled explosives under an exemption to the F.A.R's and one of the items that we flew around was rocket motors for ejection seats.These had to have periodic inspections and we often picked them up at Air Force Bases and Naval Air Satations and took them to Indian Head,MD. where the inspections took place.Later,we'd return them to the users.At that time,the Army had a fleet of OV-1 Mohawks based at FHU.
Every time that I tried to take off from Ft.Huachuca in the Beech,the wind would be blowing from what seemed to be 4 directions at once.The tower would ask which runway we wanted to use and I'd look at the wind sock and head for the one that was closest to being into the wind.By the time I'd get to the end of that runway,the wind would have changed by at least 90 degrees and was blowing at least 20kts and gusty.So,I'd head for the next most favorable runway.The same thing would happen,so I'd just take off and figure that at sometime during the take off run,I'd probably end up with a headwind component.
Nothing much had changed in that department when my c/p Chuck Ott and I arrived at FHU in Tanker 22.Other than having to struggle into the air in unfavorable wind conditions,FHU is another one of those places where everything is uphill no matter which way you go.It's lower to the north,but the fire was south southeast of the airport.I figured that the FAA should throw in a free Sailplane Rating with the B-17 Type Rating because you needed to know all of the tricks of soaring to go anywhere while loaded.I used to joke that the only aircraft with a lower rate of climb and a lower roll rate were hot air balloons and open parachutes.
It took almost 20 minutes to climb up to the fire and it took 5 minutes to get back to the airport.That part was even problem because we had to lose so much altitude in so short a distance.The pictures showing the airport from T22 were in a descent from the fire.All that we could do was to drop the gear and bring the props back to 1600 rpm and 20" of manifold pressure and take up a spiral orbit to lose altitude without building up too much speed.
Butler Aircraft's B-17 Tanker 65 had been a Navy PB-1W radar picket airplane and it still had a power chart riveted to the throttle quadrant.The lowest setting listed was "Hover" and said to use 1400 rpm and the minimum amount of manifold pressure to maintain 100kts.I only mention this because I tried that power setting one day when I had some altitude and was empty to see what would happen.The props looked like they were almost in feather and the vibrations were enough to convince me that the engines and props weren't happy.After that,I'd use 1600 rpm as a minimum.
We took about 6 or 7 loads to the fire and loaded up for one more.When we tried to start #3 engine,it wouldn't fire.It turned out to have no fuel pressure because the boost pump had failed.We checked the circuit breakers and looked for broken wires,but it was an internal failure in the pump.We called Marana and Pete,the Director of Maintenance said that he'd bring us a replacement pump,but we had to empty the fuel tank.We did that with the transfer pump by moving the fuel across the wing to #1 and 2.
The next problem was being loaded with retartant.Most tank systems have over center latches that hold the doors closed until hydraulic pressure forces the latches back over center allowing the door fall open.T22 had a Rosenbaum tank.I guess that this was supposed to be fail safe because hydraulic pressure was needed to hold the doos closed.If you lost your hydraulics,the doors would open.However,that isn't the greatest thing to have on the ground.
T22 had an additional 24 volt battery installed because the B-17 had an electric hydraulic pump.The hydraulic system on a B-17 is extremely simple (at least until you plumb in a retardant tank).The only hydraulic items are the brakes and the cowl flaps.Even the cowl flaps are an after thought that didn't show up until the B-17D model.There isn't even an engine driven hydraulic pump installed.The point being,that the hydraulic pressure would eventually bleed down and when it got to a certain pressure,the electric pump would kick in and run until the pressure was back up.So,we had to leave a battery on all night and hope for the best.I went around and removed the bulbs from all of the warning lights that wouldn't shut off in order to reduce the load on the battery.
We went to the motel and Pete changed the boost pump.The next morning,we found that the retardant doors were still closed but the battery was pretty low.Fortunately,we had another one with a full charge.We transferred the fuel back to #3 and tried to start.There was plenty of fuel pressure.Too much,actually.Instead of our normal 15 psi,we had 25.Pete said that was okay.I tried to start #3.It wouldn't fire and fuel was pouring out of the blower drain.
We called Tom Hammond at Evergreen.He said that the pumps were interchangable an that I must be doing something wrong.We checked the ignition booster and mags and found that they were okay.I was stumped and went into the standby shack and asked the other pilots and mechanics if anybody had any suggestions.John Elgin was flying Tanker 160.He said that he had a similar problem with an H-34 helicopter once,except in reverse.
What he came up with was that there are two types of boost pumps.Normally,the B-17 uses the one with 15 psi and the H-34 uses the one set for 25 psi.While it's true that they can be interchanged,the primer nozzle also has to be changed to match the pump output.In my case,the primer (which primed the blower) had too much pressure to atomize the fuel.In his it had too little.
This sounded like a good theory,so I tried an old Twin Beech trick to test it out.I got our Hudson Sprayer pressure can and filled it with avgas out of a fuel sump on T22.Then I pulled the top 5 front spark plugs out of #3 and sprayed some fuel directly into the cylinders and reinstalled the plugs and leads and tried to start the engine.It fired up long enough to get it to run on the mixture control.
We had Pete send us the correct primer nozzle as that was a lot easier to change than the pump.File this under the heading "It's always something!".
Last edited by Larry Kraus on Sat Jan 19, 2008 2:25 am, edited 1 time in total.
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