In Australian Service – Constellation

The familiar sculptured lines of the fuselage with the three tails and an efficient wing shape started to evolve. Because of the power output of the engines, relatively large 15′ diameter propellers were installed. This was one of the reasons for the development of the fuselage shape. To avoid particularly long undercarriage legs which were required to provide the necessary propeller clearance the fuselage was curved downwards at the nose. Even so, the nosewheel leg still ended up being nine feet in length. The Fowler flap which had been used on both the Lightning and Hudson was incorporated into the design. Differing from other flap configurations, the Fowler increased wing area as it extended itself from the trailing edge.

Apart from the inclusion of airconditioning and pressurisation, the model 49 was noteworthy as the first commercial aircraft to have a power-boosted flying control system. In a five-year research programme that brought the system to perfection, Lockheed engineers investigated the stick force (without boost) required by the aeroplane itself under critical conditions. They then determined the amount of muscular effort deemed most desirable by the pilots themselves. After analysing all the data, a system was devised to boost the human control effort by mechanical devices to lessen the pilot’s workload and consequently reduce fatigue.

Manufacture of the Model 49, or Constellation as it became known, commenced in 1940. The initial order was for nine aircraft placed by TWA. Pan American ordered 40 aircraft in June 1980 and TWA increased their total order also to 40 not long after. These orders were later relinquished and the USAAF was to absorb all the initial aircraft for transport use.

Development of the Constellation was delayed when the US entered World War II as Lockheed’s facilities were needed for the production of combat aircraft. When work did recommence the Model 49 had emerged as the C-69 transport for the USAAF. Construction of the camouflaged prototype was completed by December 1942. This aircraft was registered NX 67900 although it was actually USAAF aircraft No 43-10309. Crewed by Boeing test pilot Edmund T. Allen and Lockheed’s Milo Burcham with three others, NX 67900 took off from Burbank on January 9. 1943, for an uneventful 60-minute maiden flight. One of the other crew members was Lockheed Chief Research Engineer Clarence L. Johnson who was later to head the top-secret Skunk Works.

After completion of its test programme, the prototype was handed over to the USAAF at Wright Field in Dayton, Ohio, on July 29, 1943. In a way that became typical of the growth of the series the take-off weight had increased to 86,250 lb and landing weight to 75,000 lb. The USAAF ordered 180 aircraft but at the War’s end when only 15 had been accepted, the remaining military orders were cancelled. These 15 Constellations were then made available for airline use. In the post-war boom, by the end of 1945 over one hundred Constellations had been ordered by various airlines.

The first flight of the civilian version of the C-69, the Lockheed L-049, first flew on December 11, 1945. An updated variant of this was not long in coming when, on October 19, 1946, the L649 Constellation II made its debut. It was powered by the Wright R-3350 C-18BD-1 developing 2500 hp which resulted in increased performance. To improve freight capacity the “Speedpak” freight container was devised.

This was a 400 cubic feet pod that was capable of carrying up to 8200 lb of cargo which was attached to the underside of the fuselage. Gross weight was now 92,000 lb. When the L649A, with redesigned landing gear, appeared this was further increased to 100,000 lb.

In 1947, the long-range L749 emerged. Fuel capacity had grown from 4800 gallons of the L649A to 5820 gallons by fitting integral fuel tanks in the outer wing panels. The ultimate Constellation was the L749A. Featuring a reinforced wing centre section and new undercarriage, the maximum weight was now 107,000 lb. Maximum speed was 347 mph, cruising speed 275 mph at 18,000 ft, range 3050 miles, span 123 feet, length 95 feet 2 inches, height 22 feet 5 inches and wing area 1650 feet. The total production of all Constellation models, both civil and military, was 233 aircraft.

If the Constellation enjoyed the reputation of a fine airliner the next development of the series was to further enhance this. Lockheed was working on plans for a new stretched model to be known as the L1049 Super Constellation. Over 550 design improvements were made to the L 749 to bring about the transition to the Super Constellation. The original L049 Constellation prototype which had been sold to Howard Hughes was bought back by Lockheed for conversion to the Super Constellation prototype. Still carrying the original Lockheed construction number of 1961, it was known as “old 1961″. Amongst the numerous changes, the most visible alterations were an 18’5″ fuselage extension (10’9″ fore and 7’8″ aft of the wing) and enlarged tail surfaces. The registration was changed to N67900 and the first flight subsequently took place on October 13, 1950. Other major changes were a modified wing structure with integrally stiffened skin on the upper and lower wing surfaces and increased fuel capacity. Not all detail changes were incorporated into the prototype, which retained, among other things, the original round Constellation passenger windows.

When the first production aircraft, registered N6201C, made its initial flight during August 1951, other improvements were included. Larger 161/e” x 181/e” rectangular passenger windows which increased visibility by 85 per cent were fitted. Around the cockpit, crew visibility was aided by increasing the height of the seven-panel windshields by 3½ inches. To prevent both exterior ice and interior fogging these panels utilised a layer of transparent conductive coating as a heating element. The conductive Nesa (non-electrostatic formulation A) is sprayed 45-millionths of an inch thick in the inside surface of the outside 3/16 inch layer of glass. The other layers consisted of an ¼ inch centre layer of elastic vinyl and a 3/e inch layer of glass. The Nesa element operated on an input of one to four kilowatts of power. A new type of improved de-icer boot which would not “balloon out” at high speeds was fitted to the leading edges of the wings and fixed tail surfaces and extended to the 1 o per cent chord points of the airfoils. These high-pressure, all-pneumatic boots were composed of a number of tubes of tough weather-resistant synthetic rubber which were supplied with high-pressure air from two pumps.

Such was the efficiency of the redesign that the empty weight increased only by 8800 lb although the payload was up by 40 per cent. The seven fuel tanks had a total capacity of 6550 US gallons. The layout of the tanks was similar to the original six-tank system of the L749A but was added to with the additional 730-gallon wing centre section tank. The passenger area of 76½ feet out of a fuselage length of 113’7″ was the longest of any airliner available at the time.

Initial L1049 Super Constellations were powered by the 2700 hp Wright C-18-CA1 or the Wright C18-CB1 of 2800 hp. The engine which was to play such a prominent part of the Super Constellation’s history was the innovative 3250 hp Wright turbo compound Cyclone 972 TC-18DA-1. This powerplant was probably close to the limits of development for a large piston engine. Although basically similar to the earlier engines used on the Constellations, several improvements including an exhaust turbine system were included. Exhaust gases from six of the 18 cylinders flowed through three ram-air-cooled power recovery turbines which transferred this otherwise waste energy into added power for the propeller shaft. The turbine took advantage of exhaust energy without appreciably increasing back pressure and transmitted it back through fluid couplings to the engine crankshaft. The turbine wheels spun at a 6. 25:1 ratio over crankshaft speed on engines installed on L1049 models.

These engines had fairly impressive specifications. The 18 cylinders had a total displacement of 3350 cubic inches. The bore was 6.125 inches and stroke 6.312 inches, compression ratio was 6.7. Using 115/145-grade fuel maximum take-off power was 3250 hp at 2900 rpm. Maximum cruise power using a low blower was 1810-1910 hp at 2400 rpm and 1750-1800 hp at 2400 rpm using a high blower. The supercharger drive had a ratio of 6.46:1 on the low blower and 8.67:1 on the high blower. It was the military version of the Super Constellation which first used the turbo compound engine. These were the R7V-tDf of the US Navy and the RC-121C of the USAF. Initial production of these engines was earmarked for military use. In addition to the service equivalents of the Super Constellation, one other notable aircraft to be so powered was the Lockheed Neptune. Eventually, in 1953 some turbo compound engines were made available for civilian use. The first version to be so powered was the L1049C, capable of carrying up to 110 passengers with a gross weight of 130,000 lb. The structure was stressed to sustain a possible gross weight of 150,000 lb in anticipation of using more powerful turboprop engines in the future. The subsequent L10490 was marginally heavier with a gross weight of 133,000 lb and was fitted with large cargo doors. Intended to be used as a freighter, only four were built. Progressive improvements led to the L1049E and the L1049F versions.

It was the L1049G, however, which was undoubtedly the most successful of the Super Constellation series. Essentially an updated L1049E, it included various structural modifications which lifted the maximum weight to 137,500 lb. Commonly referred to as the “Super G”, it became the first commercial airliner to be equipped with wingtip fuel tanks. These 600-gallon tanks increased the range to over 4000 miles. Later aircraft in the L1049G production run were powered by the DA-3 version of the turbo compound engine with a modified supercharger developing 3400 hp. A total of 104 L1049Gs were produced. The final version of Super Constellation was the L1049H, a freighter/passenger equivalent of the L1049G. Fitted with the EA-6 turbo compound of 3440 hp, gross weight increased to 142,500 lb.

The ultimate development of the series and one of the most advanced piston-engined airliners ever built was the L1649 Starliner. This was a substantially redesigned Super Constellation with a completely new laminar flow wing. Span increased to 150′ and gross weight to 160,000 lb. Maximum speed was 377 mph at 20,000 feet. The 9600-gallon fuel capacity increased range to 4800 miles. The powerplant was the EA-2 turbo compound of 3400 hp. Hamilton Standard Hydromatic propellers of 16’10” diameter harnessed the output. The first flight of the Starliner was on October 11, 1956, the prototype being registered N1649. Although high hopes were held for its sales potential the pending arrival of the new generation of jet transports restricted total production to 44 aircraft. By the time the last aircraft of the family, an L1049H, was delivered on September 30, 1959, a total of 856 Constellations/Super Constellations/Starliners and associated military derivatives had been built.

As early as January 17, 1945, Qantas was associated with the Constellation when Hudson Fysh had a flight in an aircraft undergoing flight trials. He was impressed by what the Constellation had to offer. In the post-war era, Lancastrians were used as land-based aircraft for the Australia-England route. By modern-day standards, they were devoid of most of the comforts we would expect. Nonetheless, they provided the means of keeping the air link open. Carrying a grand total of nine passengers in sideways seating with a small quantity of mail, the economics of the service were horrifying. The annual rate of loss on the Kangaroo Route whilst the Lancastrians were used was estimated at £1,400,000.

As primitive as the Lancastrian was, the British aircraft industry just did not have any other type available to compete with the US offerings. Considerable pressure was exerted by various British authorities and personalities to entice Qantas to purchase the Avro Tudor 2. At a Qantas board meeting in Brisbane on December 27, 1945, a decision was reached to approach the Australian Government to obtain permission to buy Constellations. Communications in this matter reached the highest level when a cable was sent from British Prime Minister Clement Attlee to Australian Prime Minister Ben Chifley, requesting Qantas not to go ahead with the purchase of Constellations. Despite this, Qantas, feeling that they had no alternative, ordered four Constellations. The Tudor 2 was a doubtful quantity and certainly outmoded when compared with the Lockheed offering. BOAC themselves ordered Constellations when it became apparent that the Tudor was unsuitable for the North Atlantic service because of insufficient range. The basic cost of the Qantas Constellation was £284,532 per aircraft; with fittings, spare engines and airframe parts the estimated total cost was £2,151,572. Many Qantas technical staff were stationed at Lockheed’s Burbank factory for training purposes. Ten pilots and six first officers were the first to be so attached.

All the planning became a reality when the first aircraft VH-EAA “Ross Smith” landed at Mascot on October 14, 1947, at the end of its 33-hour delivery flight (43 hours elapsed time) which had set a new commercial record. The Constellation was to usher in a new era, bringing together speed and comfort for the first time. Although the Lancastrians operated an express Sydney-London service taking 67 hours for the journey, their comfort was questionable. A comfortable flight was certainly provided by the Short Hythe flying boats, but the Sydney-London journey took 5½ days. In preparation for the start of regular services a Sydney-London proving flight and return was made under the command of Captain R. J. Ritchie. Regular flights commenced on December 1, 1947, when VH-EAD took off for London with 29 passengers. This was notable by being the longest airline service in the world at the time, carried out without a change of aircraft. The fare was Sydney-London £325 single and £585 return.

The original order for four Constellations was augmented by the purchase of two aircraft from Air India at an approximate cost of £348,000 each. Qantas had required an additional two Constellations for some time but their inability to get an allocation of US dollars had compelled them to hunt around for aircraft available in the Sterling area. A shortage of US funds at that time made it no easy task to obtain large capital items from the USA for intending Australian purchasers.

When initially introduced into Qantas service the Constellations were fitted out to carry 38 passengers. The actual payload was 12,120 lb over ranges up to 2500 miles. Four seats were also located in the Promenade Lounge. Conversion of all the Qantas L749s to L749A standard was carried out in the early 1950s. Several were later modified to carry 60 passengers when Qantas introduced tourist fares in April 1954. Other routes were served as the fleet expanded. VH-EAD operated the first Sydney to Johannesburg flight on September 6, 1952. Services to the Orient were introduced during 1954. A different role was fulfilled by VH-EAF when it was used as a VIP aircraft during the Royal Tour of Australia in 1954.

The operation of the Constellations was not without problems.

Dogged by recurring engine malfunctions, Qantas increased their holding of spare engines from 50 per cent to 100 per cent of Those installed. At the peak of these problems, 52 per cent of the engines were removed before reaching their expected 800-hour time expired running time. Several methods were used by Lockheed for major modifications to strengthen their engine mountings and wing structure. These modifications were made necessary by the loss of two Electras in the USA through wing failure. To bridge the gap left by the temporary departure of the Electras, Qantas chartered Super Constellation N9717C (ex VH-EAI). On arrival back in Australia it was re-registered as VH-EAI and was renamed “Southern Boomerang”. After completing a six-month lease it returned to Twentieth Century Airlines on March 27, 1961, to be used as a 98-seater on MATS services.

The Super Constellation operations weren’t devoid of incident. On October 14, 1959, whilst VH-EAO was on a flight from San Francisco to New York the number four engine began to run rough. The Captain shut down the offending engine and attempted to feather the propeller. Preparations were made for an emergency landing into Lovelock Field, Nevada. To lighter­ the load, fuel was jettisoned prior to the landing approach during which, the propeller of the failed engine fell off. Fortunately, no one was injured and the aircraft was not damaged.

Engine problems did re-occur again and caused the loss of VH-EAC on August 24, 1960, in an accident at Mauritius. Engaged on the regular Johannesburg to Sydney run carrying 38 passengers and 12 crew, it commenced its take-off on the next leg to Cocos Island. During take-off, the No. 3 engine failed and the pilot, Captain E. Ditton, attempted to abandon the take-off. VH-EAC could not be halted in time before running off the end of the strip and hitting an obstruction the aircraft was substantially damaged by impact and was destroyed in the fire which broke out. All the fire drills done by the Qantas crew paid off when all the occupants were evacuated in 90 seconds. Although injuries were sustained by six passengers no one was seriously hurt.

Despite all the grace and sophistication of the Super Constellation the unreliability of its engines at times gave cause for concern. Engine malfunctions were not uncommon and, despite rigid standards of maintenance, the number of times such problems occurred was excessive. In military use, the Wright turbo compound engines were not called upon to make frequent climbs to high altitudes. It appears that repeated long climbs to cruise heights in the region of 20,000 feet imposed strains on the engines in civil use not encountered by their military counterparts. Even if an overhaul was recently completed there was no guarantee of exemption from engine troubles. If. However, the engine did reach about 70 hours without encountering problems it quite often reached its overhaul life.

It is perhaps unfortunate that piston engines have grown so large and complex. It appears that the Pratt and Whitney R-2800 installed in the DC-6 and Convair twins was the optimum size for power and reliability. The problems encountered by the Super Constellation were similar to those faced by other large four-engined aircraft, both civil and military. It is not difficult to understand ·why the emergence of the big jets with their attendant engine reliability was so welcomed by the airlines.

By late 1959 Qantas were starting to dispose of their Super Constellation fleet. Six aircraft were traded in to Lockheed in part payment for the Qantas purchase of their Electra fleet. During this phasing-out period, some of the Qantas Super Constellations appeared in different guises. Aircraft were at times on charter to TEAL and Malayan Airways. Two others, VH-EAA and VH-EAB, were used as freighters. They were flown to the Lockheed plant where they were reworked to L1049H standard.

The introduction of the Boeing 707 into Qantas operations meant the relegation of the remaining Super Constellations to secondary roles. Some were used for charter flights and the L 1049Hs commenced an all freight service from Sydney to London in 1962. By May 1963 they were finally withdrawn from Qantas use. So ended the association of the Constellation/ Super Constellation with Qantas. Spanning a total of nearly 16 years, they assisted in further promoting Qantas’ role as a major international airline.

Worldwide, there are few of models of the family to be seen in use. At the beginning of this year, there were only four Constellations and four Super Constellations remaining in service.