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Freight Dogs Finally a forum for those midnight prowler types who utilise the unglamorous parts of airports that many of us never get to see. Freight Dogs is for pilots and crew who operate mostly without SLF.

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Old 25th Dec 2016, 21:49   #121 (permalink)
 
Join Date: Oct 2006
Location: usa
Posts: 29
"Ice Pilots" demonstrate that the old girl can keep on going and do it quite well.
Ansett in Australia used a system call "combustor" to start their L-188's in remote areas. The combustor used compressed air bottles, all steel starters, injecting fuel into the starter air duct and igniting it. Flames would shoot out of a starter exhaust port in the engine cowl. Usually scare the hell out of someone that had not seen it before. Engine would spin up very fast.
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Old 26th Dec 2016, 02:48   #122 (permalink)
 
Join Date: Aug 2001
Location: Ft. Collins, Colorado USA
Age: 83
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I believe Lockheed offered some built-in high-pressure air bottles for combuster type starts. Not used on EAL Electras. Some DC-8 had a cobuster on nbr. 3 engine. 3000-psi air was stored in the MLG oleo legs in a chamber above the oleo portion. There was also a small tank of 60/40 alcohol-water that was injected, mostly to improve mass flow I think. EAL also modified on Electra by installing an APU in the aft baggage area. It was gone by the time I arrived in 1964 as it was too noisy (or so I was told). That aircraft had no aft LH fuselage pneumatic ground connection to the confusion of ground crews.
Little known fact, first few EAL Electras had provision for a speed brake on fuselage belly midships. I opened a large screw-installed belly plate for a phase-check inspection and there was a cavity under it with hinges and mounts for a hydraulic actuator and capped hydraulic fittings. Of course with those huge flat face of the props there was no need for speed brakes. Later aircraft had skin with no sign of this.
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Old 26th Dec 2016, 09:05   #123 (permalink)
 
Join Date: Oct 2007
Location: Eastbourne
Age: 78
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Yes, early build included air bottles in the wing for an engine start. I believe they were not a great success and disappeared quite quickly. Standard air start inlet was under no.3. This was also the first in the start sequence, so groundcrew had to uncouple underneath a running engine. So some airlines installed an inlet on the rear port fuselage, behind the cabin door. This was a much better option, but NOT all airlines paid for this mod. so not all aircraft had it. Various APU options were discussed to get over the need for an air start unit at route fields; I am not aware of any great success.
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Old 26th Dec 2016, 18:48   #124 (permalink)
 
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Location: Eastbourne
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Further thoughts and memories! Air bottles just supplied compressed air to the starter turbine. No combustion along with that. Another option Zantop used at one of their outstations was a large (15 ft long 6 ft cylinder) which was filled with compressed air over several hours. Supply was from a compressor attached to a car engine. This was a one shot wonder. Blew for 20 seconds or so; if you screwed up the start there was no way back! In view of this an Air Start Unit was the standard option at route fields. One foggy morning in Finland I could not get into Helsinki, so went to our company alternate Turku. Before shutting the last engine down I got ALM to check they had an ASU. Thumbs up. As No 4 wound down they asked how many volts we needed from this ASU! So one had to be trucked in from Helsinki over the day. Cost 800 from memory. Happy days
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Old 27th Dec 2016, 01:44   #125 (permalink)
 
Join Date: Sep 2016
Location: Marco Is., FL
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I kind of thought the Eastern L-188's had APUs in the tail. There was an exhaust port there with a screen over it. We were told that was to protect the APUs from 250 kt. birds flying into your rear. Maybe they were removed at some time. I have a friend at United who said they windmill started a Viscount engine at the gate with propwash from a DC-6 ( or 7 or Connie maybe ). They used ropes wrapped around the prop hubs on DC-3s also. As co-pilot on a CV 440 we checked the auto-feather of each P & W R-2800 on taxi out. You let the RPM drop a little and disarmed it did the other engine. One night at DCA, I let the RPM get a little low doing this and both engines loaded up and quit. As we coasted to a halt in front of the Atlantac Aviation ramp. The very gruff Captain said: "Gee, that never happened to me before". Ground control said: "Eastern continue taxiing...........Oh, I see you've lost them both". The ships battery was never kept in good enough condition to start those big engines and we barely got a call off to operations for a power cart as the battery voltage charged downwards from 24 v. It took them 1/2 an hour to get us started again. Miraculously I didn't get bawled out by the Captain.
A Buffalo Air DC 4 froze one night in the far north after the ground electric engine heaters tripped a circuit breaker and no one noticed until morning. They couldn't unfreeze them with the electric heaters and had to fly in a big Janitrol space heater.
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Old 27th Dec 2016, 19:10   #126 (permalink)
 
Join Date: Aug 2001
Location: Ft. Collins, Colorado USA
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Re Lolder's remark re EAL Electra's having an APU:
No, except for the one L-188 they tried an APU on, none of EAL's had an APU and that one was long gone by 1964. For off-line charters, we did have a stripped down portable GT unit that could be shipped in the baggage. It had to be removed and set up on a baggage cart. I personally never saw it.
More usable, there was also a long ground air starter hose with a coupling at each end. If you had a jet needing a start and had a second aircraft with running engines you connected them by the hose. The coupling that went into the running aircraft had a forked fitting protruding out of it. It held the flappers of the aircraft check valve installed at the ground connection open. Turn on pneumatics and you supplied the other aircraft.
Best description of a B747 with an inop APU was that it was as helpless as a whale on a beach. It required external AC power and two huffer units to get it going.
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Old 27th Dec 2016, 23:45   #127 (permalink)
 
Join Date: Sep 2016
Location: Marco Is., FL
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Being a L-188 co-pilot I wasn't concerned with all the operational details. It was a cushy job. The FE was as busy as a one arm paper hanger shifting engine RPM's and electrical buses just before and after take-off and landing. I don't remember any APU info other than the screen over the hole at the back tip of the tail cone. The L-188 was the biggest source of hearing loss on the airline. On the ramp at ground RPM they were a screaming banshee. At TO power they were the quietest. In cruise flight, there was an RPM and Phase sync for all 4 engines to reduce mid-cabin noise. When the Phase sync was on, each propeller kept the same angle relationship with the ones adjacent that was pre-calculated to produce the least noise; a very temper-mental fancy gadget.
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Old 28th Dec 2016, 21:19   #128 (permalink)
 
Join Date: Jan 2007
Location: uk
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Atlantic had an Electra with an app. Fitted in aft lower fuselage. Rearly used as it was unusual not to get an air starter.

As for the prop sync and top temp control. Way too advanced to have been designed in the 50s. Convinced the systems were stolen from some wreckage at Roswell.
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