Zeppelin-borne fighters

[Martin Bennitt]

While everyone else was watching the thrashing of Man Utd tonight I was taking in a documentary on the Arte channel here in France about the post-war US airships Macon and Akron and their Sparrowhawk fighters, and very interesting it was too.

anyway, to stay on topic there was all too brief mention of German experiments during the war with fighters slung below Zeppelins. Unlike the Sparrowhawk of course they could not return to the mother ship once launched, but I'd be interested in any more input from these from our forum experts.

thanks and cheers Martin B

[centurion]

Bit late tonight but there were British experiments with a Camel slung under a rigid airship. Also a fatal experiment with a Be2 to be released from a static balloon. If no one else come up with this sooner I'll post 2morrow evening with details

[Adrian Roberts]

On 26th January 1918 an Albatross DIII was released from the Zeppelin L35, at a height of about 5000 feet.

The experiment worked to that extent, but with no way of transferring between the two craft, not only did the aeroplane pilot have to stay in his cockpit for the whole flight, but the aeroplane engine had to be running the whole flight as there was no way of starting it in mid-air, so the configuration would have not have been feasible in practice.

Also a fatal experiment with a Be2 to be released from a static balloon.

This presumably refers to the AP1 concept: an anti-Zeppelin device where a complete BE2c was suspended under the envelope of an SS-type non-rigid airship, and was to be carried aloft to a greater height than the BE could normally reach and then released. The only time this was tried, on 21 Feb 1916, the aeroplane inverted when the release mechanism malfunctioned, killing Cdr N F Usborne and Lt Cdr deC W P Ireland.

[Martin Bennitt]

thanks gentlemen, that's an interesting start

cheers Martin B

[centurion]

This presumably refers to the AP1 concept: an anti-Zeppelin device where a complete BE2c was suspended under the envelope of an SS-type non-rigid airship, and was to be carried aloft to a greater height than the BE could normally reach and then released. The only time this was tried, on 21 Feb 1916, the aeroplane inverted when the release mechanism malfunctioned, killing Cdr N F Usborne and Lt Cdr deC W P Ireland.

The account I've read states that the nose released but the tail hung up and the crew were flung out. The tail then released and the plane crashed.

[Martin Bennitt]

The experiment worked to that extent, but with no way of transferring between the two craft, not only did the aeroplane pilot have to stay in his cockpit for the whole flight, but the aeroplane engine had to be running the whole flight as there was no way of starting it in mid-air, so the configuration would have not have been feasible in practice.

Sorry if I'm being a bit naïve here, but could the propellor not just windmill with the engine off, then start it when the ignition was switched on at the appropriate moment, or something similar?

cheers Martin B

[centurion]

There were a series of experiments aimed at finding a way for ships to recover land planes without having a landing deck. The idea was to use a long steel cable suspended between booms out from the side of the ship. The aircraft would fly under and along the cable so that a claw arrangement on the centre section would engage the cable. This would grip the cable and bring the plane to a gradual halt before the end of the cable was reached. It was also realised that the same mechanism could be used for launching aircraft. With the decision to produce aircraft carriers with flying off and landing capabilities this approach seems to have withered on the vine. Howether the concept was tranfered to the rigid airship, one of which was fitted with a cable running below the keel. A suitably modified Camel was suspended from the cable and, in theory, could both be released and recovered in flight. Just how far this work was carried I'll have to wait until tonight to check but there is certainly a photo of the airship with a camel attached and I believe that at least one launch was achieved.

[MikB]

Sorry if I'm being a bit naïve here, but could the propellor not just windmill with the engine off, then start it when the ignition was switched on at the appropriate moment, or something similar?

cheers Martin B

Don't think the slipstream at Zepp speed would've been strong enough to rotate the prop against cylinder compression, unless there was (eg.) a valve-lifter operable from the cockpit. Even if there had been, it's not obvious that the prop would've had enough momentum to start the engine when the pilot dropped the lifter.

The Albatros may've been different, but there was a short video about the Camel on here a while back that certainly drove home the point about how primitive and lacking in controls aero-engines were then.

Regards,

MikB

[centurion]

Don't think the slipstream at Zepp speed would've been strong enough to rotate the prop against cylinder compression, unless there was (eg.) a valve-lifter operable from the cockpit. Even if there had been, it's not obvious that the prop would've had enough momentum to start the engine when the pilot dropped the lifter.

The Albatros may've been different, but there was a short video about the Camel on here a while back that certainly drove home the point about how primitive and lacking in controls aero-engines were then.

Regards,

MikB

I believe a Camel could start its rotary by goung into a steep dive after release to get the prop and engine rotating fast enough, not sure if this would work with an Albatros DIII (and German built DIIIs had a tendency to shed the lower wing in a steep dive, the better contsructed KuK manchines might hae been safer)

[centurion]

Bit more - in the summer of 1918 a 2F1 Camel piloted by a Lt Keys was air launched from R23. Keys started his engine in the manner I suggested in my earlier posting. In 1925/6 R33 was used for experiments with a DH Hummingbird which could be launched and retrieved using a cable system. The following year R33 was equiped with 2 Gloster Grebe fighters. Unfortunately in 1928 R33 succumbed to metal fatigue.

[MikB]

...(and German built DIIIs had a tendency to shed the lower wing in a steep dive, the better contsructed KuK manchines might hae been safer)

I thought that was the DV version - but then I'm remembering the back of an Airfix kit pack from about 1957, so it's just possible I might not have the full picture on failure conditions and variants affected...

The Camel, of course, had the full weight of the engine windmilling with the prop, so would have plenty of angular momentum to overcome compression providing there was a way to get the rotation started. None of the Albatroses had rotaries AFAIK.

Regards,

MikB

[Martin Bennitt]

Thanks again for your input

anyone got any piccies?

cheers Martin B

[Doc2]

Bit more - in the summer of 1918 a 2F1 Camel piloted by a Lt Keys was air launched from R23. Keys started his engine in the manner I suggested in my earlier posting. In 1925/6 R33 was used for experiments with a DH Hummingbird which could be launched and retrieved using a cable system. The following year R33 was equiped with 2 Gloster Grebe fighters. Unfortunately in 1928 R33 succumbed to metal fatigue.

R-23r carried out more work like this, as well. According to Mowthorpe, "on 6 November 1918, two "ships camels" were released, piloted by two officers from 212 Sqd RAF".

My references, like Centurion's, report that the first aircraft associated with R33 was a DeHavilland Hummingbird, which was dropped twice successfully, but which failed to reconnect in flight (Oct 1925). On 4 Dec 1925, a successful hookup was accomplished. The Gloster Grebes were then used starting in October 1926. On 26 Oct 1926 both the Grebes were dropped, but no attempt was made to hook up in flight. Doc

[centurion]

I thought that was the DV version - but then I'm remembering the back of an Airfix kit pack from about 1957, so it's just possible I might not have the full picture on failure conditions and variants affected...

The Camel, of course, had the full weight of the engine windmilling with the prop, so would have plenty of angular momentum to overcome compression providing there was a way to get the rotation started. None of the Albatroses had rotaries AFAIK.

Regards,

MikB

DIII and DV suffered from the same problem. I've seen a paper discussing this - it seems that the German built versions had a lower wing that was too flexible and tended to suffer from flutter and finally collapse. The Austro Hungarian versions had a more rigid construction and did not have the problem . This was purely a matter of factory/inspection tolerances rather than any actual difference in design. Albatross didn't really understand wing design and some of the later Cs suffered from excessive wing generated drag that nullified the effect of the finely streamlined fuselages

The rotaries were intended to be switched on and off in flight. Diving ought to have generated enough airflow over the prop to do the job. However I wonder how the radial engined Grebes on R33 managed. None of the production Albatrosses had rotaries (from memory at least one rotary engined prototype was built but I'll check 2night.)

[centurion]

Thanks again for your input

anyone got any piccies?

cheers Martin B

http://upload.wikimedia.org/wikipedia/comm...AirshipR23.jpeg

http://www.airminded.net/camel/camel_r23.jpg

[centurion]

And

http://airminded.org/wp-content/img/aircraft/r33-grebes.jpg

[Martin Bennitt]

Found the following in the Flight magazine archive

In the summer of 1918 it was decided to conduct experiments

to provide our own rigid airships with adequate means of defence

against enemy aeroplanes. It was intended that an airship should

carry with her a single-seat fighter which could be released and

flown when the need arose. The first experiments were conducted

at Pulham. The airship concerned was the R.23, and the fighter

was the Sopwith 2F.1 Camel.

A special horizontal surface was attached to the keel of R.23.

The upper wing of the Camel fitted snugly up against this surface,

which spanned the distance between the Camel's interplane struts;

and the attachment between aeroplane and airship was made by

a quick-release hook which passed through the central cut-out in

the Camel's centre section. The aeroplane attachment fittings

were made by No. 212 Squadron, R.A.F., Great Yarmouth.

Camels used in these experiments were N.6622 and N.6814.

The first test was made with a Camel which had its controls

locked and carried a dummy pilot. The release was accomplished

satisfactorily, and a live drop was then made by Lt. R. E. Keys,

D.F.C., of No. 212 Sqn. He was able to start his Camel's engine

after release and flew round the airship before landing safely at

Pulham. The Armistice removed the need for such devices and

almost eclipsed Keys' achievement. The Germans subsequently

claimed that they had dropped an aeroplane from the Zeppelin

L.35 in 1917. Experiments in Britain were abandoned until the

end of 1925, but thereafter were not pursued. The Americans

used the device on some of their airships in later years.

cheers Martin B

[Martin Bennitt]

L35 seems to have been favoured for experimentation. This seems to have been the world's first stand-off bomb. Think there 's a thread on it somewhere on the forum.

http://warandgame.files.wordpress.com/2007...emtopglider.jpg

cheers Martin B

[centurion]

One of a whole series (some mono planes). Intended to be used from one of the R planes (possibly the Siemens Schuckert RVIII) the largest Siemens Schuckert Torpedoglieter was a monoplane 1,000Kg model. Intended for anti shipping purposes they are not so much predecessors of stand off bombs but the glider missiles used by the Luftwaffe in WW2.

[centurion]

None of the production Albatrosses had rotaries (from memory at least one rotary engined prototype was built but I'll check 2night.)

In late 1918 there were two prototypes of the Albatross DXII rotary engined fighter. Much earlier somewhere between 5 and 10 Albatross rotary engined LI scouts entered service.