Buy A Mature Rocket Or Design A New One?

Buying a mature rocket technology gives companies the designs and hardware know-how, but not necessarily the decades of engineering wisdom needed to make it work.

Buying mature rocket technology is not just about getting drawings, tooling, documents, training from the seller/transferor and access to the seller's testing facilities and other resources.

But the big question is the transfer of undocumented accumulated knowledge and wisdom of engineers over the past several decades, said a former chairman of the Indian Space Research Organisation (ISRO) and other rocket experts.

Globally, there have been very few publicly documented cases of the sale or purchase of complete mature rocket technologies.

Governments have traditionally imposed restrictions on the transfer of such technologies as they are similar to missile technology, while there are also challenges in assimilating the transferred technology.

For instance, in the US, foreign nationals may be employed by space agencies and companies, but access to certain controlled rocket technologies, technical data and drawings is restricted under export-control regulations.

It is also not known whether India has imposed conditions such as restrictions on the employment of foreigners and on showing rocket drawings to non-citizens on private companies.

ISRO's Technology Transfer Initiative

Be that as it may, the Indian National Space Promotion and Authorisation Centre (IN-SPACe) has invited Expressions of Interest (EOIs) from industries for the technology transfer of ISRO's mature Polar Satellite Launch Vehicle (PSLV) and Launch Vehicle Mark-3 (LVM3).

Earlier, ISRO, NewSpace India Ltd (NSIL) and IN-SPACe had entered into an agreement with public sector Hindustan Aeronautics Ltd (HAL) for the transfer of Small Satellite Launch Vehicle (SSLV) technology.

The agreement, signed in September 2025, covers the transfer of SSLV technology to enable HAL to independently manufacture, integrate and launch the vehicle.

Training in SSLV technology has also been provided to HAL.

Prior to this, NSIL had contracted the HAL-L&T consortium for the end-to-end production of five PSLV-XL rockets with technical support from ISRO.

The first industry-realised PSLV is yet to fly. This production arrangement is distinct from a complete technology transfer of the kind being undertaken for SSLV.

Acquiring rocket technology is not akin to automobile technology

In the case of a car, the specifications are relatively standardised and do not vary with the weight of the passenger, fuel level, destination, software and other factors.

The car may be slower when the passenger’s weight increases and may consume more fuel. But the passengers would reach their destination.

"In the case of a rocket it is not so. Every rocket is designed based on the weight of its payload/satellite, its orbit and other aspects.

"As a result, the rocket's fuel quantity, avionics software and the like would differ from rocket to rocket. There is nothing called routine launch. Every rocket launch with a satellite is unique," an expert in rockets retired from ISRO told this writer.

For example, if the rocket's payload weight goes up, the launch vehicle must carry additional propellant -- not only to lift the payload but also the additional propellant added for that purpose.

In many launch vehicles, propellant accounts for 85%- 90% of the lift-off mass.

"It is extremely difficult to understand the intricacies of rockets and satellites. Problems would surface when testing is done.

"To solve that multi disciplinary teams covering the entire gamut of activities are needed.

"A seller of rocket technology can handhold the buyer for some period after that it may be an issue," retired ISRO chairman G Madhavan Nair told this correspondent.

"The key to success is not manufacturing. Integration and testing assure proper working. There are many internal processes which is trained over generations," Nair added.

"Integration of various systems is not simple and needs a lot to understand. The engine and stage must be married seamlessly, it has some common dynamics, which must be learned," another retired senior ISRO official not wanting to be quoted told this correspondent.

Assimilation Questions for Buyers

There are some assimilation questions that a buyer would like answers to, and the most important will be "how much of undocumented knowledge would be transferred by the engineers of the transferor".

The other questions are: Does the company receive the complete design and manufacturing documentation?
Will experienced ISRO personnel train the recipient company? For how long?
Can the buyer use ISRO/Department of Space facilities while establishing its own facilities?
Can Indian suppliers reproduce every critical component reliably?
Can the buyer reproduce ISRO's quality-control and acceptance regime?
If the transferred launch vehicle fails, does the buyer possess the analytical capability to determine why? This is particularly important because failure-analysis expertise is itself a form of rocket technology.

What happens when the buyer wants to modify the launch vehicle? If the original developer retains critical design authority, the buyer hasn’t really acquired complete technological independence.

Transferring Wisdom Gained Over Generations

Industry experts said making hardware is not an issue. The major problem will be the transfer of knowledge and wisdom.

Knowledge can be documented, but the wisdom gained over generations from seniors cannot be put down. It can be used only when a situation arises.

So, a rocket technology buyer may get the documents, drawings, tooling and other material but not the wisdom from the seller/transferor.

"At times we had to search and locate a long-retired person to solve a technical issue. The specific knowledge and wisdom is passed down by the people working in one department to others in the same department," the retired ISRO official said.

Officials are of the view that the knowledge-assimilation challenge may be less pronounced in solid-propellant launch vehicles such as the SSLV.

But where liquid-fuel and cryogenic engines are involved, the issue becomes more critical.

"When India got the cryogenic engines from Russia for its Geosynchronous Satellite Launch Vehicle-Mk I (GSLV Mk I), it was the Russian engineers who were involved in integration, ISRO officials were not allowed near the Russian cryogenic engine," a retired senior ISRO rocket expert recalled.

So, whether one buys the technology of a whole mature launch vehicle or even one or two rocket stages, the know-how assimilation for the buyer will be a major challenge.

Designing from Scratch vs. Technology Transfer

According to industry experts, it would be better for space companies to design their own rockets from the ground up than buy a mature one whose technology is several decades old.

However, another retired senior ISRO official told this correspondent that Indian space startups need not get disheartened as there is a large talent pool of retired ISRO officials who can take over teaching of the technology and pass on the wisdom to the technology buyer's engineers.

"The learning curve of the engineers in the start ups will get shortened and may not take several decades.

"Many retired ISRO officials have been engaged by the rocket companies in India, a fact that is not known to people at large," the official added.

Private companies, he said, are innovating, including through 3D-printed engines and other technologies.

So, learning the intricacies of a mature rocket may not be very difficult now, or an effective alternative approach may be found.

There is a need to increase the production of rockets, and involving industries through technology transfer is the only way out, he added.

While it took several years for ISRO to come out with PSLV and later with SSLV, Indian space start-up Skyroot Aerospace has, within a relatively short period, designed and built its Vikram-1 rocket and successfully carried out its maiden orbital flight in 2026.

ISRO said Vikram-1 was developed as a four-stage rocket with three solid stages and a liquid stage and successfully placed payloads in Low Earth Orbit.

ISRO and IN-SPACe also provided handholding and access to testing and other facilities for the venture.

According to the retired ISRO official, this is one indication of the talent pool available in India that could shorten the learning curve.

As a matter of fact, ISRO's Vikas engine, which powers several of its rockets, has its origins in the Viking engine technology transferred by France.

ISRO subsequently assimilated, adapted and further developed the technology for its launch vehicles.

This shows that technology transfer, when successfully absorbed and developed further, can eventually contribute to indigenous technological capability.

On the other hand, proponents of the 'do-it-yourself' approach are of the view that buying a mature technology, manufacturing the rocket and then launching it commercially could be a gamble.

Nevertheless, the debate continues.

Venkatachari Jagannathan can be reached at venkatacharijagannathan@gmail.com

Feature Presentation: Rajesh Alva/Rediff