Devices manufactured using a tool patented by a Lithuanian are still on the surface of the Moon


The genius of welding systems Gasparas Kazlauskas is unknown in Lithuania, and it seems he has never been such here. Radioisotope thermoelectric generators (RTG) produced with the help of the welding tool he has designed and patented were flew with the Apollo 12, 14, 15, 16, and 17 to the surface of the Moon and left there for the rest of the days.

Saulius Lapienis

Apollo 13 was also carrying an analogue generator to the Moon, however, the mission was unsuccessful due to explosion of an oxygen tank: astronauts were not able to land on the surface of the Moon and the crew returned to Earth following emergency procedure. The lunar module with the RTG inside landed to Tonga Trench in the Pacific Ocean to the south from Fiji, where it still rests in the depth of 6.9 km (the exact location is unknown).

On a popular website Answerbag, one can find a question “Who invented the orbital** tube for welding?” Below presented is the answer: “Gasparas Kazlauskas is the inventor of the orbital tube welding head. At the time of his invention in the 1960s, he worked for North American Aviation as a senior mechanical design engineer working with resistance welding. The Space Nuclear Auxiliary Power (SNAP) project used this welding tool.”


Biography of Gasparas Kazlauskas

Mr. Kazlauskas was born on 10 December 1922. He lived and worked in Los Angeles, California where he died on 24 May 2009. Unfortunately, even in this digital age, I could not find a picture of Mr. Kazlauskas.

XB-70, “Valkyrie” nuclear  power bomber

Mr. Kazlauskas worked as a senior mechanical design engineer in the company North American Aviation (NAA), and engaged in contact welding. NAA was the major producer of aerospace technology in USA, which has designed more than one historical aircraft:

T-6 Texan trainer aircraft, the P-51 Mustang fighter, the Mitchell B-25 bomber, Sabre F-86 jet fighter aircraft, X-15 rocket-powered aircraft, XB-70 nuclear bomber, also the command and service modules for Apollo, second stage of the Saturn-V rocket, Space Shuttle, and the B-1 Lancer bomber. The company eventually became a part of Rockwell International, and currently it is a part of Boeing.

When working for NAA, Mr. Kazlauskas was assigned to design a device required for the Systems Nuclear Auxiliary Power program, or the SNAP 1/2 project. He was required to produce a bundle of compressed D-shaped tubes. The diameter of the tubes was 71.12 cm in the upper part, and 35.56 cm in the lower part, and the length was 3.048 metres. Electricity is generated as a reaction between two different environments, i.e. +426°C sodium inside the tubes, and the cosmic cold of –240°C outside.

The device for orbital tube welding

With the help of the device invented by Mr. Kazlauskas, the tubes could be welded in the bundle. Later, engineer was appointed to work on the XB-70 nuclear bomber program. In 1958, it was planned to produce 60 of such devices, however, later the number was reduced to 11, and in 1960, only 2 were required. The flight of the first XB-70 Valkyrie bomber was accomplished on 21 September 1964, and on 14 October 1965, the three times the speed of sound was achieved. The second bomber first flew on 17 July 1965, however, on 8 June 1966, Valkyrie crashed following the fault of F-104N NASA chase aircraft during while flying in a multi-aircraft formation.

For some time, NASA continued experimental flights with the first bomber, however, after 4 February 1969, it was put to a museum. The only one remaining XB-70 bomber can be found at the national National Museum of the United States Air Force at Wright-Patterson Air Force Base near Dayton, Ohio.

Despite the cuts in the XB-70 program, Mr. Kazlauskas continued working on the orbital welding technique. He has reduced the size of the device to such an extent it became a prototype of the modern orbital welding heads.

On the website A history of Welding (, section The Greatest Welders of the World, beside the world-class celebrities, such as the Italian author Vannoccio Vincenzio Austino Luca Biringuccio, who wrote on the history of metallurgy and was the author of pyrotechnics (1540), Ukrainian inventor Nikolai Nikolaevich Benardos (mid-19th c.), who has invented the modern day welding, English inventor Elihu Thomson (1885) who has invented contact welder, German inventor Johann Wilhelm Goldschmidt (1899) who has invented thermit welding, American inventor Russell Meredith (1942) who has invented arc welding, and the father of nickel brazing American inventor Robert Peaslee (1951 m.), one can see the biography of American inventor G. Kazlauskas (6th decade of the 20th century), who has invented the orbital welding head.

The award catalogue issued by the American Welding Society in 2010 specifies that the inventor Kazlauskas was awarded AIRCO welding awards for the originality of new products and innovations while applying welding technique in 1972 and 1973.

Orbital welding, RTG and SNAP

Valkyrier muziejuje
“Valkyrie” XB-70 nuclear bomber at the National Museum of the United States Air Force at Wright-Patterson Air Force Base near Dayton, Ohio

Welding tools that were available before 1960 did not satisfy the quality requirements applied to seams in hydraulic systems subsonic aircrafts that flew at the speed of sound. Defects occurred continuously. Welding tools that were used for circular or round welding were very large and installed permanently indoors, and therefore they could not be used outside the walls of the factory. Electrodes needed to contact and heat the welding seam for several times. This encouraged the industry of aeronautics and space to order a new and more efficient orbital welding. Constant improvements that were carried out around 1960 resulted in the development of a compact, portable, and automated orbital welder that performed welding tasks by a single touch. Since then, orbital welding has been used for production of different equipment and materials used in the industry of aeronautics and space, shipbuilding, automotive industry, biotechnology, chemical technology, pharmaceutical and food industries. Orbital welding is also used in the semiconductor industry for producing “cleanroom” components, and also for production of heavy industrial equipment containing metal pipes and tubes.

In 1955, extensive scientific research on using nuclear energy in space was initiated. As a result of these efforts, the first radioisotope thermoelectric generators (RTG) were designed to perform tasks of atomic power plant in space and for special tasks on Earth. In radioisotope thermoelectric generators, heat obtained from naturally occurring radioactive fission is transformed into electric power. RTG operates under the principle of thermoelectricity whereby heat is directly transformed into electricity. This principle was discovered by German scientist Thomas Johann Seebeck in 1821. He has noticed that in a close contour, when different temperature is maintained at the junction of two metals, electric current is generated. Such pairs of metals are called thermo-electric pairs or thermocouples. In 1960, USA launched the program titled Systems Nuclear Auxiliary Power System which involved experimental radioisotope thermoelectric generators and cosmic nuclear reactors. In USA, radioisotope thermoelectric generators are numbered using odd numbers, and compact nuclear reactors are numbered using even numbers. We have already mentioned that the invention by Mr. Kazlauskas has contributed to the occurrence of SNAP-1 and 2 (SNAP-1 was not further developed and was not implemented into spacecrafts). Rankine cycle*** used cerium-144, and mercury as heat-transfer fluid which functioned successfully for 2500 hours. Experimental reactor SNAP-2 was the second reactor in the SNAP group. The fuel used for this device was uranium-zirconium hydride; reactor’s design capacity – 55 kilowatts. This was the first model that was used in flight control unit; experiments were carried out from April 1961 to December 1962. In 1961, the first RTG used in a space mission was launched aboard a U.S. Navy transit navigation satellite. The electrical power output of this RTG, which was called Space Nuclear Auxiliary Power (SNAP-3), was a mere 2.7 watts. But the important story was that it continued to perform for 15 years after launch. Since that initial SNAP-3 mission, RTGs have been an indispensable part of America’s space program.

Beside RTG, radioisotope heater units (RHU) are also used. They were used for the mission Apollo 11, Pioneer 10/11, Voyager 1/2, Galileo, and Cassini aircrafts. Three small RHU were implemented into NASA space aircraft Mars Pathfinder launched on 4 December 1996.

Low power RTG were intended for supplementing the main non-nuclear power supplies of space aircrafts, however, with the improved technology they started to perform the function of the main power supply. Currently, spacecrafts with the incorporated RTG are travelling around the Sun and Earth, and explores the planets outside the solar system. RTG were also landed on Mars and Moon (5 units).

Apollo experiments on the surface of the Moon

The first radioisotope device to be used for lunar missions was radioisotope heater implemented into the Early Apollo Surface Experiments Package (EASEP) that was prepared for work and left permanently on the Moon by the astronaut Buzz Aldrin. Šildytuvą for the mission Apollo 11 was produced by the company Bendix far on the 5 November 1966. It was used for heating up electronics components of the device used for seismic experiments. During the 340-hour-long lunar night, temperature fell to 173°C, and the 15-wat (W) heater would maintain the temperature of –54°C, i.e. the minimum temperature below zero at which electronic devices are still operable. The heater was 7.6 cm in diameter, 7.6 cm in height, and weighted 57 grams.


Seismograph weighted about 45 kilograms. However, it worked only 21 day until it went off due to overheating on a hot sunny day. For the sake of interest, it should be noted that the seismograph of a simple structure was sensitive enough to record movements of sleeping Neil Armstrong.

Upon starting the mission Apollo 12, the Apollo Lunar Surface Experiment Packages (ALSEPs) were transported to the Moon. SNAP-27 with the implemented RTG with what you can call nuclear batteries was used or the operation of these packages. The tubing inside them was welded using the technique of orbital welding.

The list of the Early Apollo Surface Experiments Packages (EASEPs with the implemented RHU) and the Apollo Lunar Surface Experiment Packages (ALSEPs with the implemented RTG) that were flew and left on the Moon


Apollo 11

Apollo 12

Apollo 13****

Apollo 14

Apollo 15

Apollo 16

Apollo 17


 appolo11  appolo12  appolo13  appolo14  appolo15  appolo16  appolo17

Date of landing

20 July 1969

19 November 1969

****on 15 April  1970, it was closest to the Moon – 254 km.

Following a breakdown, it returned to Earth

5 February 1971

30 July 1971

21 April 1972

11 December 1972

Landing site on the Moon

Sea of Tranquillity



Ocean of Storms

3° 0′ 44.60“S;

23° 25′ 17.65“W

Fra Mauro

3° 38′ 43,08″S;

17° 28′ 16,90″W

Close to Apennine mountains

26° 7′ 55,99″N;

3° 38′ 1,90″E

Descartes Highlands

8° 58′ 22,84″S;

15° 30′ 0,68″E


20° 11′ 26,88″N;

30° 46′ 18,05″E

Place of the package on Earth

The great (Pacific) Ocean,

Tonga trench,

6.9 km depth




Package operation duration, and date of shutdown

Shut down by itself on 25 August 1969.

2 years.

Shut down on 30 September 1977 by remote control

Had not been put into operation

Planned operation time – 2 years. It had operated for 5–8 years until 30 September 1977 when NASA shut down the power plant by remote control

Type of power plant

Thermal – ALRHU

Electric – SNAP-27 RTG


2×15 W

Electric power

63–73 W, 16 V DC

Had not been put into operation

Electric power 63–73 W, 16 V DC


Patents obtained for the inventions of the Lithuanian author

Gasparas Kazlauskas is the author of 25 patents, and 23 of them are attributed to the B23K technology group “Soldering Or Unsoldering; Welding; Cladding Or Plating By Soldering or Welding; Cutting By Applying Heat Locally, E.G. Flame Cutting; Working By Laser Beam”. Among the most prominent and most significant patents by Mr. Kazlauskas is the patent No. US 3395262 “Kazlauskas’ external weld head” issued 30 July 1968. Another significant patent is the one issued 3 September 1968 – Patent No. US 3400237 “Kazlauskas’ welding head”, that describes the melt-through welding technique.

Patents by Gasparas Kazlauskas have been used by the famous companies, such as Astro-Arc, Boeing, BASF, Cajon, ESAB, Delphi, D. L. Ricci, Eisenmann, Framatome (Areva and Siemens), General Electric, Kobe steel, Magna, Magnatech, Mantra, Minesota Mining and manufacturing (current name 3M), NASA, Norsk Hydro, O. J. Pipelines, Saipem, Swagelok, Tri Tool, United technologies, Westinghouse Electric and others.

The patent No. US 4373125 “Apparatus for welding pipes” issued to Mr. Kazlauskas on 8 February 1983 had been used by 33 world-famous corporations from India, Italy, United Kingdom, Japan, USA, Canada, Norway, Holland, South Korea, Sweden, Switzerland, and other.

The list of the patents obtained by Gasparas Kazlauskas

Date of issue


Patent co-authors




Owner of the patent

1968 07 30




North American Rockwell Corp.

1968 07 30




North American Rockwell Corp.

1968 09 03




G. Kazlauskas

1972 08 29




G. Kazlauskas

1972 11 14


M. E. Gedgaudas*



Astro-Arc Co.

1972 11 14


E. P. Vilkas



Astro-Arc Co.

1973 12 04




Astro-Arc Co.

1974 09 10




Astro-Arc Co.

1982 12 21


V. J. Jusionis ir kt.



Messer Griesheim Industires Inc.

1983 02 08




Messer Griesheim Industires Inc.

1983 04 12




Messer Griesheim Industires Inc.

1983 10 04




Messer Griesheim Industires Inc.

1984 01 24




Messer Griesheim Industires Inc.

1984 10 09




Messer Griesheim Industires Inc.

1985 08 27




Messer Griesheim Industires Inc.

1985 11 19




G. Kazlauskas

1985 12 03




G. Kazlauskas

1987 03 10




G. Kazlauskas

1987 11 03




G. Kazlauskas

1988 02 23




G. Kazlauskas

1988 08 09




G. Kazlauskas

1989 05 07




G. Kazlauskas

1989 08 15




G. Kazlauskas

1990 01 30




G. Kazlauskas

1990 05 30




G. Kazlauskas

Patents by Gasparas Kazlauskas were cited for almost 200 times in other copyrighted documents.

While working on separate patents, Gasparas Kazlauskas cooperated with three Americans of the Lithuanian origin – Vytautas J. Jusionis, Eugene P. Vilkas and Mindaugas E. Gedgaudas. And the fourth one, Linas A. Martinėnas referred to three patents by Kazlauskas in his own patent “Small size tube welding apparatus” (No. US 5841089, 24.11.1998). Moreover, M. E. Gedgaudas is the president of the leading company in orbital welding Arc Machines Inc. (AMI). The welding machines manufactured by this company were used for welding USA spacecraft fuel tanks, and the company AMI was granted an acknowledgment from Lockheed Martin for this for performing this task. AMI has performed welding tasks on fuel supply system of China-Brazil Earth Resources Observation Satellite CBER-2. It should be noted that the company performs welding tasks on the hydraulic and fuel supply systems made of titanium on the fastest business class aircraft Citation X (Cessna Aircraft Co.).

The story of the engineer Gasparas Kazlauskas is an example to follow. The inventions made by this inventor when developing a device for interplanetary space flight equipment have been used not only for space industry, the development and production of military and civil aircrafts but many other areas of industry. In the future, we are planning to present more success stories for the readers pf the journal.


Steven Aftergood, Background on Space Nuclear Power, Science &Global Security, 1989, vol. 1, pp. 93-107

George D. Cremer, ALSEP SNAP-27 RTG Beryllium assembly (Apollo 12), San Diego, California

The role of Nuclear Power and Nuclear Propulsion in the Peaceful Exploration of Space, IEAA, Vienna, 2005


* The first manned mission Apollo 1 ended with the tragic death of all the astronauts. After this catastrophe, all the subsequent missions AS-202, AS-203 and Apollo 4, 5, 6 were not manned. The mission Apollo 18 which entailed docking of Apollo spacecraft with the then-Soviet Soyuz 19 spacecraft in the Earth’s orbit was not a lunar mission.
** Orbital welding is a method of automated arc welding, whereby a welding arc moves around a round subject of welding, and the very subject of welding remain static. This method is applied for welding tubes of the diameter from several millimetres to several centimetres
*** Rankine cycle is a theoretical thermodynamic cycle that involved four main operations: liquid evaporation at high pressure, steam expansion, steam condensation, liquid pressure increase to the initial value.

The article prepared as a part of the project “Encouraging local and international scientific cooperation, and competence development” funded by the European Social Fund and the Ministry of Education and Science.

About this project

This publication prepared by „Aviacijos pasaulis” aviacijos_pasaulis_logo