Indigenous 180hp Diesel Engine May Power Tapas UAV for Taxi and In-Flight Trials, Promises Long-Endurance in High-Altitude Environment

In a major boost to India's self-reliance in defence technology, Coimbatore-based Jayem Automotive has developed a powerful new diesel engine specifically designed for unmanned aerial vehicles (UAVs).

This 180hp engine, unveiled at Aero India 2025 in Bengaluru, has successfully completed ground trials and is ready for integration into the Tapas UAV (Tactical Airborne Platform for Aerial Surveillance).

Company officials have confirmed that the engine is being installed in the upgraded Tapas UAV, with taxi trials and in-flight trials expected to commence soon. This development marks a significant step towards reducing India's dependence on imported engines for its UAV programs.

The new engine addresses a critical need for high-performance, indigenous power plants for MALE (medium-altitude, long-endurance) UAVs. Compared to conventional gasoline engines or imported alternatives, this 180hp diesel engine offers several key advantages:

• Enhanced Endurance: Diesel engines are inherently more fuel-efficient, allowing UAVs to fly longer and cover more ground. This is crucial for surveillance and reconnaissance missions where extended flight times are essential.
• High-Altitude Performance: The engine is designed to operate efficiently in oxygen-thin environments, making it ideal for missions in high-altitude regions like the Himalayas, which are strategically important for India's border security.

This indigenous engine is expected to significantly enhance the capabilities of the Tapas UAV, enabling it to perform long-duration surveillance and reconnaissance missions in challenging high-altitude environments.

 

[sanket]

That's good news! Indigenous engine for Tapas. Congrats, Jayem Automotive, for developing the engine!

 

[obiwankenubi jedi]

Very good! Let's see how it works! And if the jinxed RUSTOM-2/TAPAS BH201 is finally resurrected and literally rises from the ashes! We can then rename it project Phoenix! It has been effectively sabotaged for decades now to favour foreign OEMs and the arms dealers!

 

[GMR]

So exciting...maybe Rustom will be able to achieve the predefined parameters with this engine...unless concerned people have made up their mind to import.

 

[AK S]

So exciting...maybe Rustom will be able to achieve the predefined parameters with this engine...unless concerned people have made up their mind to import.

Challenges will be there on both fronts.

Tech Front: Flight ceiling of 30K ft with meaningful payload using piston engines is not realistic. It challenges the limits of physics. There isn’t enough oxygen to burn the fuel. Gasoline and diesel require similar oxygen levels…so diesel won’t help much there. We can’t use an oxygen concentrator…meaningful payload will be impacted. However, the range/duration part should be addressed with these diesel piston engines.

Interest Group: With Adani championing Israeli MALE UAVs, it’s going to be an uphill task for TAPAS or even Archer NG. Physics affects Israelis equally, and they can’t and don’t fly to advertised heights with any meaningful payload and duration. But then they are well entrenched and very well represented.

 

[Dredd]

Challenges will be there on both fronts.

Tech Front: Flight ceiling of 30K ft with meaningful payload using piston engines is not realistic. It challenges the limits of physics. There isn’t enough oxygen to burn the fuel. Gasoline and diesel require similar oxygen levels…so diesel won’t help much there. We can’t use an oxygen concentrator…meaningful payload will be impacted. However, the range/duration part should be addressed with these diesel piston engines.

Interest Group: With Adani championing Israeli MALE UAVs, it’s going to be an uphill task for TAPAS or even Archer NG. Physics affects Israelis equally, and they can’t and don’t fly to advertised heights with any meaningful payload and duration. But then they are well entrenched and very well represented.

Aren't Diesel engine heavier compared to gasoline, rendering extra power and efficiency ineffective?

 

[alpha numeric]

An engine with a similarly rated hp has been on DRDO's website for quite a while. If this is anything more than just a mockup, then it's a win for us.

 

[IndiJoe]

Aren't Diesel engine heavier compared to gasoline, rendering extra power and efficiency ineffective?

Bingo! They are. And my guess is that this is where the decision makers would have signed off on a compromise.

What happens if you don't make the traditional, heavy cast iron blocks for a diesel engines? What happens if you use some new age lightweight but strong metal alloys (hint... MIDHANI) instead to build such an engine? Possibly you get an engine which may not have the large lifespan of a traditional diesel engine and yet will last long enough to support an expected lifetime of a MALE UAV.

Also, diesel engines can operate with a wider fuel to air ratio as compared to gasoline engines. There are enough research papers on this including from MIT that has decisively proven that diesel engines are way more efficient than gasoline engines at higher altitudes where the air starts thinning out. So there...Don't be surprised if this diesel engine actually manages to take Tapas higher, figuratively as well as literally speaking!

Afterall, making 180hp diesel engine isn't such a big deal today. What possibly Jayem has been engaged in to is a venture into the unknown territory and yet extract the optimum out of a path breaking idea.

 

[Sandeep]

This engine was developed based on the Tapas drone weight, fuselage and size etc which has now been scrapped. It’s highly unlikely that we can repurpose this engine for the Archer NG drone which is a single engine and has a twin boom configuration.

The best option is to issue a license to several private sector companies who can manufacture and sell the engine to other customers. Then we can recover the research cost by accepting a royalty fee.

 

[chakra]

Great news. Hope it delivers the required thrust and altitude.

 

[Shanker]

Is there a possibility of developing such engines of higher power to substitute the imported propeller engines for basic trainer aircrafts to start with?

 

[venk11]

Very good...congrats for future taxi...
May in coming time we can use this for social use to relief from traffics and all...

Good luck to see there...👍👌