High-Tech

The best of both worlds

When the Super Star entered service in 1957 it was regarded as the most advanced airliner of the era. As a high-tech product made by the famous Lockheed aircraft company, the L-1649A was flying higher, faster and further than any other piston engine powered long-distance airliner manufactured in the late 1950’s.

Over the last six decades, the technical standard of aircraft manufacturing has developed in a dramatic way. This primarily concerns the areas of propulsion techniques, materials used for the manufacturing of aircraft and the technical standard of flightdeck instrumentation.

All these advancements resulted in the aircraft being the safest of all means of transportation on a global scale!

Although the Lufthansa Super Star has its roots in 1957, the year of construction, it is currently being overhauled and equipped by Lufthansa Technik AG according to the highest current safety standards applicable to aircraft manufacturing and overhaul in the 21st century. Thereby the Super Star project in a remarkable way is building the bridge way between six decades of aviation technology.

During this metamorphosis the L-1649A transformed from a pure analog aircraft of the 1950’s to a unique combination of an analog and digital high-tech product of the present. This is enabled by Lufthansa Technik’s status as an approved design organization in combination with the outstanding know-how of its global workforce.

 

This unique expertise offered by the leading company in the fields of aircraft overhaul, repair and maintenance was – and still is – required in many areas of the Super Star restoration.

Future LSSG passengers will find it difficult to tell the grade to which high-tech of our millennium has been applied during the overhaul process of the Super Star built in 1957. Just a look into the flightdeck will reveal how the original pure analog aircraft, built before the advent of the computer age, has been combined in an impressive way with the achievements of the digital age.

 

In the early days of the Super Star project, the cockpit designers of Lufthansa Technik had already planned a re-arranged L-1649A flightdeck to ensure that the planned certification would be in the highest category as commercial passenger aircraft. Only thereby is guaranteed that LSSG passengers will be able to conquer the world in style on board the L-1649A. This anticipated certification brings the Super Star to the same high level as the rest of the Lufthansa Airline fleet.

The original, more than sixty year old cockpit instrumentation design did not correspond to the high demands of the certification authorities. Furthermore it didn’t allow the adaptation of contemporary safety and human factor standards.

The obvious solution would have been to complement the historical displays by modern instruments, but the lack of space in the narrow Super Star nose excluded this desirable option. Alternatively the Lufthansa Technik flightdeck team of experts opted for the combined presentation of primary flight instruments on modern screens in a digital glass cockpit. This proved to be the best compromise between current safety requirements and the scarcely available space.

In close cooperation with the project engineering and the US authorizing authority FAA the experts of Lufthansa Technik in Hamburg developed a concept that not only lives up to the highest standards but preserves as much legacy as possible.

The new design is based on an avionic suite, originally developed for the Lockheed C-130 „Hercules“ transporter, and donated to the project by its manufacturer Honeywell. The Honeywell Flight Management System sends all necessary flight data to the so called Flight Director which transfers these inputs into visual pilot displays. The modern Honeywell avionic furthermore supplies data to the original Bendix PB 20 autopilot of the 1950’s.

Apart from the obvious invention of four big displays, two each on the captains and first officers side, other flightdeck areas have been adapted. One item being the overhead panel above the pilots heads, now ergonomically sorted with cutting-edge lightplates and switches in style of current Airbus or Boeing standards. Another being the modern radio management units, located to the left and right of the pilot seats. 

To assure a safe flight operation, the Super Star combines the best of the analog world of the 1950’s, with the digital advancements of our age.

Technological world premiere!

The Lockheed L-1649A project is filled with an array of superlatives and extraordinary achievements. Like the fusion of the best of both worlds, not only in a proverbial sense, presented by the example of the Super Star cabin door overhaul.

As a technological world premiere it has been possible for the very first time to unite ultra modern and historical aluminium alloys by the means of resistance spot welding. Needless to say all safety requirements imposed by the surveying authorities as well as the LSSG and Lufthansa Technik teams have been met.

 The reason for this venture was door “one right”, which is constructed in a sandwich form as are all Super Star doors. The outer door skin is welded with a deep drawn corpus, giving the door the necessary strength to withstand the artificial cabin pressure at high altitudes. In the course of the overhaul process taking place at the Lufthansa Technik workshops in Hamburg, the inner and outer door segments were separated, revealing irreparable cracks and signs of corrosion on the inside of the corpus. The only way was to rebuild the corpus with modern aluminum alloys and weld it again to the original outer skin. This demanding process was meticulously planned by the project engineering, members of the FAA and the team of experts supplied by Lufthansa Technik. The welding process itself was executed by a partner company, to the full satisfaction of everyone involved.

As there was no literature or experience available how to connect vintage aluminium alloy with modern alloys, the Super Star project team had to pioneer the process. Before risking working with the original material, the welding experts produced 154 standardized test plates consisting of different materials and welding techniques. By means of this test series the resistance spot welding turned out to be the preferred choice.

After the successful combination of the structural elements, door “one right” was equipped with the opening mechanism and shipped to Auburn for installation to the Super Star.

Installed a while ago, today nothing reminds us of the world premiere associated with this door. This instantly successful repair is another example of the unique know-how to be found in the Lufthansa Group!

Reverse Engineering

Only the best in the business have been chosen to work on the Super Star. But sometimes, even the greatest personal experience and most sophisticated technical devices, needed to ensure a safe component overhaul, are unable to deliver immediate answers. Leaving nothing to chance, in these rare cases the Super Star component team trusts in ‘reverse engineering’.

The Super Star team is determined to seek a solution for even the biggest challenges. Like the rebuild of eight jackscrews, driving the wing flap mechanism. As all of them were out of limit, only a new fabrication of these flight safety relevant parts was deemed possible.

It is essential for the technical team to understand the production method applied by Lockheed in the 50’s, which isn’t described in the original technical documentation. The only way to gather this crucial information was a metallurgical examination by electron microscope of the parts in question. Only this insight view, down to the molecular level, delivered the desperately needed answers in terms of safety margins, expected lifetime, applicable flight cycles, weight and rigidity.

Based on these scientific examinations, Lufthansa Technik, in cooperation with a partner company, ‘reverse engineered’ replacement jackscrews being at least as good as the original parts when leaving the factory in the 1950’s. Though only eight new jackscrews are needed for installation on the aircraft, two further samples have been ordered for qualification tests. Again, nothing is left to chance, as the meticulously calculated and fabricated parts have to prove the correctness of the theoretical calculations in exactly defined qualification tests. The gathered calculations and test results are finally presented to the FAA as certification agency. Only when the FAA as final instance has given its go-ahead, the reverse engineered jackscrews will be installed on the Super Star.