Royal Flying Corps 1917 Guided Rocket?

[PMN1]

Wandered into this from another board

British unmanned aerial vehicles of World War I - Wikipedia

en.m.wikipedia.org

Archibald Low stated "in 1917 the Experimental Works designed an electrically steered rocket... Rocket experiments were conducted under my own patents with the help of Cdr. Brock"[16] Like Low, Brock was an experimental officer. Brock commanded the Royal Navy Experimental Station at Stratford. Pertinent to these rocket experiments, Brock was also a Director of the C.T. Brock & Co. fireworks manufacturers. The patent "Improvements in Rockets" was raised in July 1918 referring by then to the Royal Air Force. It was not published until February 1923 for security reasons. Firing and guidance controls could be either wire or wireless. The propulsion and guidance rocket eflux emerged from the deflecting cowl at the nose. The 1950s IWM exhibition label states "Later in 1917, an electrically steered rocket was designed…. with the designed purpose of pursuing a hostile airman." A model of this dirigible rocket was included in this exhibition.[17] The model was accompanied by a note: "Exhibit that is part of Professor AM Low's exhibits. Model of the wireless controlled dirigible rocket missile designed to pursue a hostile airman."


Anyone have any more information on this?

 

[Dilandu]

Found the patent Low was mention & the description of the rocket here:



It's a rather crude design of ground-launched guided rocket that, according to author, could be used either to shot down enemy planes, or to throw a safety lines to victims of maritime disasters (yeah, a typical early XX century patent). Basic ideas:

* The rocket is controlled by a direct current wires, switching the polarity cause the electromagnets onboard the missile to turn the rudders (horizontal and vertical) in one or other direction.

* The rocket is "forward-firing", i.e. nozzles are pointed forward, and the ejected gases are deflected backward from cone-shaped cowl. Apparently such design was chosen to have a rocket tail free for control surfaces.

* Author also mention the possibility of wireless control, but did not get into details.

Essentially, a whole design is rather crude, without any significant details (like roll control, for example). Apparently Low was more interested into getting a patent as fast as possible, "or someone else would think about it", and not into detailed development of his concept. I strongly suspect that no work on this design was actually done, and the model in Royal Flying Corps exhibition was made merely to "illustrate" the concept.

 

[Temistocle]

Hi, here a model of the rocket, the picture is below:

 

[Dilandu]

Hi, here a model of the rocket, the picture is below:

Yep, but it seems it's a later, illustrative model, rather than any kind of experimental prototype.

 

[Temistocle]

Yes, as I said (and the IWM page says too) it is only a model.
The inscription on the base is:

Model of the world's first steerable rocket design
Major A. M. Low
RFC Experimental works 1917
Presented by Research Engineers LTD

 

[PMN1]

Does the idea sound viable for the time?

 

[DWG]

Wire-guidance had been around for almost 40 years at that point, cf the Brennan torpedo, and we had recent experience of monitors being attacked by German wire-guided Distance Controlled Boats (which the RN was interested in replicating) . So the guidance technology isn't actually new, it's the combination with rockets that's new, and rockets clearly worked (and had been working in military use for over a century).

 

[Dilandu]

Does the idea sound viable for the time?

Without any kind of roll stabilization - no, it wouldn't work. The command guidance required for missile & operator to be in agreement where is "up" and "down", "left" and "right". If the missile i rolling uncontrollably, the directions would also change rapidly, and no control would be possible (imagine what would happens if operator gave "up" command while missie is upside-down)

Some kind of roll stabilization is, therefore, required. Problem is, those things aren't simple & free. The missile could be made roll-stabilized by placing a dihedral wing on it (aerodynamic stabilization), but in that case the missile would likely be pretty hard to steer (too stable). Alternatively, the mechanical roll stabilization could be used - such as gyroscope autopilot, or mercury oscillator - but they would make missile significantly heavier and more complex.

 

[Cthell]

Without any kind of roll stabilization - no, it wouldn't work. The command guidance required for missile & operator to be in agreement where is "up" and "down", "left" and "right". If the missile i rolling uncontrollably, the directions would also change rapidly, and no control would be possible (imagine what would happens if operator gave "up" command while missie is upside-down)

Some kind of roll stabilization is, therefore, required. Problem is, those things aren't simple & free. The missile could be made roll-stabilized by placing a dihedral wing on it (aerodynamic stabilization), but in that case the missile would likely be pretty hard to steer (too stable). Alternatively, the mechanical roll stabilization could be used - such as gyroscope autopilot, or mercury oscillator - but they would make missile significantly heavier and more complex.

Given the way the control cable attaches to the underside of the tail of the missile, I wonder if there was an idea that the weight of the trailing cable would act as keel to stabilise in roll?

 

[Dilandu]

Given the way the control cable attaches to the underside of the tail of the missile, I wonder if there was an idea that the weight of the trailing cable would act as keel to stabilise in roll?

I rather doubt that. Most likely Low simply did not thought this out. The whole project is extremely basic.

 

[Scott Kenny]

Without any kind of roll stabilization - no, it wouldn't work. The command guidance required for missile & operator to be in agreement where is "up" and "down", "left" and "right". If the missile i rolling uncontrollably, the directions would also change rapidly, and no control would be possible (imagine what would happens if operator gave "up" command while missie is upside-down)

Some kind of roll stabilization is, therefore, required. Problem is, those things aren't simple & free. The missile could be made roll-stabilized by placing a dihedral wing on it (aerodynamic stabilization), but in that case the missile would likely be pretty hard to steer (too stable). Alternatively, the mechanical roll stabilization could be used - such as gyroscope autopilot, or mercury oscillator - but they would make missile significantly heavier and more complex.

While true, the Sidewinder managed to get away with some amazingly basic rolleron gyros, which were novel in application but not all that novel in design.

 

[Dilandu]

While true, the Sidewinder managed to get away with some amazingly basic rolleron gyros, which were novel in application but not all that novel in design.

True, but rollerons, while mechanically simple, aren't exactly technically simple. First of all, to be efficient, they need to rotate fast. On Sidewinder, it was achieved by missile being supersonic; the early XX century blackpowder missile would not be fast enough. It could be solved by having some apparatus to spin rollerons before launch, but it would be complicated.

Secondly, it would require a very fine quality bearings for rollerons to spin. While the required quality was accessible in early XX century, it likely wasn't cheap enough for single-use projectile.

Thirdly, rollerons must be heavy to efficiently stabilize the missile. Which means either cutting into missile other characteristics, or putting more strain on motor. And early XX century rocket engines - before efficient nozzles were developed - just weren't efficient at all.