Ghost Connie, you're cleared for flypast," calls the tower as Captain Charles "Chuck" Grant drops the nose of the Lockheed C-121C and asks flight engineer Jerry Steele for more power. The four turbo-compound Wright R-3350-93s howl louder and the Super Constellation thunders along the crowd line at El Toro, in California, at 200kt (370km/h) and an altitude, at one point, as low as 150ft (45m).
With the exception of fighters such as the North American P-51 and Curtiss P-40 Kittyhawk, the C-121C is faster than most of the other massed "ghosts" in the circuit.
Keeping company with "warbirds" and plying the air-show circuit is the major source of revenue for this ex-US Air Force Military Air Transport Service (MATS) aircraft, but things could change, according to owner Benny Younesi. "Operating costs are about $3,000 per hour, including fuel, maintenance, parts and insurance. If we could utilise the aircraft at more than just air shows, we could reduce that cost, and getting insurance to do that is one of the most important priorities for us right now." The aircraft appeared at more than 12 air shows in 1996 and is expected to be flown at 15 in 1997.
"If we can make $3,500/h, or $500/h profit, then we'll go, but there are times when we barely break even," says Younesi. "We'd like to install at least 40 seats and put it in VIP configuration for charter operations, or, alternatively, get a company that would be willing to sponsor the Connie," he adds.
There are plans to take it on a European tour in mid-1998, starting and finishing in the UK. "So far, we haven't found any sponsors, but we keep looking," he says.
Flight International joined the crew in April at El Toro Marine Corps Air Station in southern California to experience a typical air-show day. Grant, a veteran pilot with 38,000h experience (25,000h of which have been on piston-engined aircraft) was assisted by Pat Farrell, a private pilot whom Younesi sponsored for his Super Constellation type rating. They formed the flightcrew, along with Steele.
The flightdeck gives a cramped impression, despite Lockheed's remodelling of the Model 1049/C-121 which increased the height of the seven-pane windscreen by more than 80mm and provides an extra 180mm of headroom in the cockpit. Pilot instrumentation is limited to flight instruments and dual manifold pressure (MAP) and RPM gauges on the centre panel. All other engine, fuel, hydraulic and electrical instruments are on the side-facing flight-engineer's panel.
Start-up
We started the number 3 and 4 engines first, sending clouds of exhaust smoke towards the crowd line. Most smoke was emerging from the lower cylinders, where quantities of unburned oil had accumulated since the previous flight. Engines 3 and 4 drive pumps which power the second of the Constellation's two hydraulic systems. The second system operates the landing gear, wing, flaps, brakes and the nose-wheel steering. The primary system, driven by engines number 1 and 2, drives the flight controls. "In the event of a multiple pump failure, we have a cross-over switch on the flight-engineer's panel," says Grant, who first checked out on a Trans World Airways Lockheed Model 049 in 1947 . "If one side is running empty, everything just runs a little slower," he adds.
The Constellation also has electric auxiliary-boost pumps, one for the elevator and the other for the rudders, to serve as back-ups for the primary-system pumps during the critical stages of flight - take-off and landing. Finally, there are boost-valve-disconnect levers for the three control surfaces, which allow the pilot to take manual control in the event of a primary system failure. "It's an old-fashioned boost system which makes it heavy-handed to ßy at the best of times. If the boost fails and you've got to go manual, it takes two guys all they've got to give it 10í of bank," says Grant.
Flight conditions
The aircraft was taxied to the run-up area behind a Boeing B-17 and turned into wind. With oil temperatures above the prerequisite 40¹C, the outboards (No 1 and 4) were run up first. After the magnetos were checked (with a maximum allowable drop of 75RPM), these engines were retarded back to around 1,000RPM - enough to keep their DC generators on line. While No 2 and 3 were being checked, the co-pilot "bled" the primary hydraulic system by holding each flight control in full deflection for around 30s.
Flaps were selected at the last minute to keep demand on the second hydraulic system low, with several steep taxi turns yet to be accomplished. The Super Constellation's large Fowler flaps were then selected to 60%, which moved them aft, rather than down. Auxiliary boost switches were turned on as we lined up for take-off on the most northerly of El Toro's parallel runways. With the B-17 airborne, the take-off run began. At our light weight of 44,550kg, our V1 speed was 95kt and V2 around 115kt.
Looking at take-off
Grant advanced the throttles and called for take-off power. Steele set this up by closing the cowl flaps from their full open position, setting the throttles at 48in manifold pressure (MAP) at sea level (1.62bar or 23.6lb/in2) and checking for 2,900RPM. He also watched the BMEP gauges (a measure of torque) to hold 220 and not exceed 228. The co-pilot held the yoke fully forward and Grant assumed directional control as soon as the rudders became effective. Nose-wheel steering was maintained to V1, however, in case of a critical engine failure. "I'm looking for an overboost on torque, or a drop in manifold pressure. Both will tell me more quickly than RPM if I've lost an engine," says Steele.
With each R-3350 setting up an appropriate howl, the empty Super Connie raced along the runway, the torching exhaust visible even in the bright morning sunlight. At V2, the aircraft lifted rather than rotated, and Grant called for gear "up". From the outside, the left main gear seemed to take longer to retract than the right, and it appeared even to fall back slightly before retracting. This is caused by the proximity of the right gear to the pumps of the secondary hydraulic system, plus restrictor valves, which deliberately retract the right gear first.
As the indicated airspeed increased to 130kt, Grant called for maximum continuous except for take-off (METO) power. Steele set MAP at around 47in and checks against a BMEP exceedence of 215. At 500ft, with the aircraft turning into the right-hand circuit over the surrounding orange groves, the flaps were retracted and speed built up to 160-165kt. The engines were behaving well, despite their age and complexity. The R-3350s are each fitted with three power recovery turbines (PRTs). Each shrouded PRT is turned by the exhaust of six cylinders and transfers its energy back to the main crankshaft through a fluid coupling, thereby recovering what would otherwise be wasted energy. At take-off, each PRT contributes up to 110kW (150hp), adding around 340kW per engine.
"The engines are the most troublesome because they have so many moving parts, and they're old. Even brand-new ones could be a problem and, in its hey-day, the Connie was often called the world's best tri-motor," says Steele. "We get a maximum of 3,000hp out of them today. At its prime, it put out between 3,200hp and 3,600hp. We have to use unleaded fuel now, which does not help," he adds. To prolong life, Steele has also deliberately de-tuned the engines, advancing the spark by 5¹. By altering the angle of the magnetos, the gases in the cylinder "-light off a little sooner, so we're not compressing the gases as much. This means we're not putting out so much power, but it extends the life. We try to baby them".
Apart from engine wear and tear, "-our biggest expense is fuel", says Steele. "We average 600 US gal [2,275litres] for the first hour and, after that, between 300 and 400 gals at around $2 a gallon," he says. The Connie also consumes copious quantities of oil. In addition to each engine's individual 136litre tank, there is a 250litre auxiliary tank which can be diverted to supply any engine in flight. "We can go through between six and 10 gal/h. In the good days, it would be more like three to four. We're actually throwing more oil than we're burning, because these engines just aren't as tight as new ones," Steele says.
After several circuits, it was time to land and, with airspeed slowing to 185kt, flaps were selected to "take-off" position. At 130kt, power was set at 27in MAP and 2,400RPM for approach. (There was no pulling throttles back to idle, as is the case in today's aircraft.) Grant said "my throttles", and called for gear extension. "You don't lose much speed with the gear down, but once you put them and 100% flap down it really slows," he comments. With final approach speed stabilised at 120kt, full flap was selected at about 150ft, necessitating some rapid rolling back on the trim wheels from the crew. The flaps claw 10kt from the aircraft speed and, over the fence, speed was down to 110kt. "Much lower than that and the elevators are not effective," says Grant.
Maintaining power
Power is kept on until over the "numbers", and the throttles were pulled all the way back once in landing attitude. Elevator control was moved aft, with elevator trim to help keep the nose up until the main gear touched down, which, seconds later, it did in a firm manner. The spindly nose leg was lowered gently and the propellers reversed on the inner two engines to help shorten the landing run. Clearing the runway, cowl-flaps were opened, auxiliary boost turned off and flaps retracted as we followed a Heinkel 111 which was limping along on a deflated tyre after a heavy landing.
The engines were idled briefly before shut-down at 800RPM to scavenge the oil system - a rather hopeless exercise. After engines 3 and 4 were shut down, the brakes were shifted to the "emergency" system because, according to the Lockheed manual, they would lose pressure in 15-20s. Finally, engines 1 and 2 were shut down and another short, but very sweet, flight in the Super Constellation was over.
The Constellation Historical Society can be contacted at e-mail: dmitchC121@msn.com
Source: Flight International
