Top Tech – The Flying Transformer

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Technology: Stop-Rotor Rotary Wing Aircraft

Agency: Naval Research Laboratory


What is it?

The Naval Research Laboratory (NRL) has developed a patented system and method of transitioning an aircraft between helicopter and fixed wing flight modes.  It’s called the Stop-Rotor Rotary Wing Aircraft.  This one in particular is a multi-purpose unmanned aircraft that can do what only toys used to be able to do; change shape.  So to speak.

What does that mean?

See the picture?  It does that.  This system turns a plane into a helicopter.  Now, my first thought when I saw this was one of those James Bond car/plane/helicopter/dirigible/spaceship vehicle things that he has (Aston Martin notwithstanding).  This is clearly a more reasonable approach to that concept, and arguably less costly.  Sorry, Q.  They’re like turbo transforming UAVs.  I like it.

What does it do?

The stop rotor aircraft is capable of both a helicopter mode – vertical takeoff and landing (VTOL) –  and efficient high speed fixed wing flight.  How?  By flipping the left wing/rotor blade 180 degrees between flight modes (obviously). Conversion between flight modes will take about 1-2 seconds and simulations indicate altitude deviations of less than 50 feet.

It’s also practical from a fuel standpoint.  Under sponsorship of the Office of Naval Research (ONR), a prototype battery electric aircraft is being developed that is capable of over 30 minutes flight duration and a cruise speed of 100 knots. Hybrid power systems could provide much greater duration and range.

How can this help?

Yes, let’s talk about the benefits.  Being able to switch flight modes on-the-fly (I couldn’t help myself) is more than just a little advantage.  If cartoons have taught me anything, it’s that those skills come in handy a lot.  Also the 38 inch long removable payload bay can carry up to 25 lbs.  We’re talking about a small, maneuverable, energy-efficient aircraft that can deliver small loads when necessary.

This aircraft can operate at efficient high speeds, and at long range unmanned aircraft without runway or other large launch and recovery systems (such as catapults and nets).  There would be reduced wear and tear compared to a regular helicopter since rotary wing flight time will typically be minimized.  It’s also smaller.  Smaller is good.

The gas turbine propulsion could enable efficient high subsonic cruise at altitudes not practical with pure rotary wing aircraft.  So really, it can boldly go where few rotary wing aircraft have gone before.

My take?

Anything that can multitask like this thing can is a plus.  The ability to switch modes as needed is necessary with so many types of technology and equipment.  Aircraft should be no exception.

This kind of technology is something that needs to be utilized and utilized and utilized.  It’s sort of a way of getting more “bang for your buck” and it’s efficient.  This is the type of machine that I would have dreamt about having as a kid.  An aircraft that can transform into a helicopter?  That runs on eco-friendly fuel?  Oh come on.  You cannot say that isn’t totally cool.

Will the Stop-Rotor Rotary Wing Aircraft help me to defend the planet against evil transforming robots and speak to me in a powerful baritone?  Probably not.  Would I be thrilled and amazed to see it convert from plane to helicopter mid-flight?  Every single time.

The fact that this is useful and awesome is what makes this whole thing so much better. This can be used on unmanned aircraft missions that require the flexibility of VTOL combined with high speed and long range.

So do it, folks.  Create these transforming UAVs.  Make whole fleets of these bad boys.  And send one my way, will ya?  It’s hard to top “hybrid transforming aircraft” in the circles I run in.  Or anywhere, really.

Or at least name ONE of them Optimus Prime.


Want to learn more?  Click here for more information on this technology!

Are you interested more federal inventions? The Naval Research Laboratory has a broad portfolio of technologies that are available for commercialization. Visit their official website to learn more!


Jessica L. Tozer is a blogger for DoDLive and Armed With Science.  She is an Army veteran and an avid science fiction fan, both of which contribute to her enthusiasm for technology in the military.

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