Airborn Aircraft Carriers. Akron, Macon.

[Uyraell]

These were effectively the last military Zeppelins to fly, being part of Germany’s “War Reparations” to the USA.

Count Ferdinand Von Zeppelin designed them for the US Navy, and doing so must for him have been a bitter-sweet experience, since he had wished to loft his airships on Helium for nearly 20 years.

The airships were designed for long range patrol, each carrying 4 or 5 (of some 12 produced) Curtiss Sparrowhawk biplane fighters, powered by radial engines, and deliberately manufactured without an undercarriage, but replacing that device with what amounted to an “overcarriage” arrangement that allowed the Sparrowhawk fighter (as it became known) to be hoisted onboard the airship from below to be re-armed and refueled, while the pilot rested.

A much later variant of the same idea later gave rise to both the McDonnell Douglass XF85 Goblin parasite fighter in the Convair B36 bomber, which concept itself evolved further into the FICON series of experiments. The XF 85 experiments were not a success, it being that the increase in airspeed since the 1920’s had brought with it a whole new series of aerodynamic issues
relating to two aircraft travelling in extreme proximity and attempting to merge. The FICON experiments were, on the whole, much more successful, yet overtaken by the vast technological leap forwards of the early-mid 1950’s, and were thus abandoned, mainly because Air-to-Air Refueling/In-Flight-Refueling had by then become an operational reality.

To return to the Akron and Macon: Both were lost in the late 1920’s, early 1930’s, one, apparently to the then little-known windshear, the other to apparent lightning-strike.
The wreckage of one was discovered on the seabed not far from the Atlantic end (if memory serves) of the Panama canal some years ago.
Divers have, as far as I know, investigated the wreck, though I have neither encountered mention of nor know of any plans to raise/salvage anything thereof/therefrom.

As time goes by, I will add to this thread, and cordially invite others to do so.

Regards, Uyraell.

[Major_Walter_Schmidt]

Pic I found:

[Uyraell]

@Major_Walter_Schmidt

Pic I found:

Domo-Arigato, Schmidt!
I recall those pics, from books in My youth, though in truth have not chanced upon them in many long years.

`Tis a distinct pleasure to see them again, and My profound Thanks to you.

Interestingly, the “approaching the trapeze” pic from above the Sparrowhawk is taken of one of the preproduction carried-hawks, still configured with conventional undercarriage.
I’d forgotten the details in the trials fighters.

Regards, Uyraell.

[Major_Walter_Schmidt]

Youre Welcome!

Anyhow, dont those things remind you of star wars?

[Uyraell]

Rather much, though in a vacuum environment none of the aerodynamic issues exist, even if mass and momentum remain.
Interestingly, other airborne carry concepts spring to mind. Short Bros. Mayo-Mercury, the various Misteln (incl. the jets Projekts), I had thought of leading off a thread in those also, but felt small steps first were the wiser path.

Kind Regards, Uyraell.

[Major_Walter_Schmidt]

I think Panzerknacker already had a thing on the Mistels…

[Skip]

The Akron was built by Goodyear and crashed april 4, 1933.
The Macon was built by Goodyear and crashed Feb 12, 1935.
They both carried 5 planes.
The Los Angeles was built by the Zeppelin company and was stickened Oct 24, 1939 and then scrapped. I look at the Macon’s hanger almost every day. It is a pleasure to look at.

[Uyraell]

@Skip

The Akron was built by Goodyear and crashed april 4, 1933.
The Macon was built by Goodyear and crashed Feb 12, 1935.
They both carried 5 planes.
The Los Angeles was built by the Zeppelin company and was stickened Oct 24, 1939 and then scrapped. I look at the Macon’s hanger almost every day. It is a pleasure to look at.

Thank you for the update, Skip:) , and welcome to the thread.

Regards Uyraell.

[Uyraell]

Here are some further pictures and data for the Curtiss F9C2 Sparrowhawk fightercraft carried By the Akron and Macon. It seems that up to 5 Sparrowhawks could be carried in each airship, which would mean it had been intended 12 be produced. This is the origin of the “12” I used in the OP.

The Data is taken from Wiki:
However: it is consistant with data I have seen elsewhere, and I find no reason to doubt it.

Regards, Uyraell.

Curtis Sparrowhawk (F9C2) specifications.
(Akron & Macon Airship-carried) Parasite Fighters.

General characteristics
Crew: 1
Length: 21.08 ft (6.27 m)
Wingspan: 25.5 ft (7.75 m)
Height: 10.92 ft (3.34 m)
Wing area: 185 ft² (16.1 m²)
Empty weight: 2,114 lb (959 kg)
Loaded weight: 2,776 lb (1,259 kg)
Powerplant: 1× Wright R-975-22 radial engine, 415 hp (310 kW)
Performance
Maximum speed: 176 mph (153 knots, 283 km/h)
Range: 297 mi (258 nm, 475 km)
Service ceiling: 19,200 ft (5,853 m)
Rate of climb: 1,690 ft/min (8.6 m/s)
Wing loading: 15 lb/ft² (78 kg/m²)
Power/mass: 0.15 hp/lb (240 W/kg)
Armament
Guns: 2 × 0.30 in (.30-06 Springfield cal.) Browning machine guns

Data, Akron, Zrs-4.

Name: USS Akron
Ordered: October 6, 1928
Laid down: October 31, 1929
Launched: August 8, 1931
Commissioned: October 27, 1931
Maiden voyage: September 23, 1931
Fate: Crashed in severe weather on April 4, 1933
General characteristics
Tonnage: 221,000 pounds (100 t)
Length: 785 feet (239 m)
Beam: 132.5 feet (40.4 m) (diameter)
Height: 152.5 feet (46.5 m)
Propulsion: Eight 560 horsepower (420 kW) gasoline-powered engines mounted internally.
Speed:
50 knots (93 km/h; 58 mph) cruising
72 knots (133 km/h; 83 mph) maximum
Range: 10,580 nautical miles (19,590 km; 12,180 mi)
Capacity: Useful load
182,000 pounds (83 t)
Volume
6,500,000 cubic feet (184,000 m3)
Complement: 89 officers and men
Armament: seven machine guns
Aircraft carried: four aircraft

Data: USS Macon, Zrs-5.

USS Macon ZRS-5
Launched: 21 April 1933
Commissioned: 23 June 1933
Struck: 26 February 1935
Fate: Crashed following structural failure on 12 February 1935.
General characteristics
Class and type: Airship
Tonnage: 108 tonnes (106 LT; 119 ST)
Length: 239 m (784 ft)
Beam: 40.5 m (133 ft) (diameter)
Height: 44.6 m (146 ft)
Propulsion: 8 internal combustion engines, 420 kW (560 hp) each
Speed: 140 kilometres per hour (76 kn; 87 mph) maximum
Capacity:
Useful load
72 tonnes (71 LT; 79 ST)
Volume
184,000 m3 (6,500,000 cu ft)
Complement: 91
Aircraft carried: five F9C biplanes.

Curtis Sparrowha&#119.txt (683 Bytes)

Data, Zrs-4, Akro&#110.txt (798 Bytes)

Data, USS Macon, Z&#1.txt (620 Bytes)

[Rising_Sun]

This is all new to me.

Am I correct in interpreting the picture as showing the observer trying to hook the trapeze onto corresponding points on the aircraft while the unseen pilot maintains position under the airship?

[Uyraell]

RS* my friend, the Sparrowhawk is a single seat fighter.
The picture shows the pilot guiding the retrieval hook onto the trapeze, which is then retracted into the airship, bringing the fighter onboard. One of the many unusual characteristics of the Sparrowhawk is that, though a biplane, both mainplanes attach to the fuselage, at top and bottom (spine and keel) respectively. The pilot in effect sat with his head and shoulders above the plane of the top wing.
To the casual viewer, the pilot thus appears as though he might be a secondary crewman ie, observer, and it is easy to assume that presence of a second person who is piloting the aircraft. In fact, there was no space in the fighter for two men, it being that its’ dimensions are little more than a Kingswood stationwagon in either span or length. This was a very small aircraft, indeed, as small as some of the 1930’s air-race airplanes.
The “pick-up hook” is guided on to the trapeze, where it engages with a positive lock, The trapeze then retracts.
This same system was resurrected for the XF85 Goblin and B36 Peacemaker combination in the 1950’s.
However: what was readily accomplished in the 1930’s at speeds of 70 mph was a far different proposition in the 1950’s, at speeds above 250mph. Whereas in the 1930’s there was in effect insufficient speed to concern either airship or fighter, side-gusts notwithstanding, there was next to no airflow-boundary layer turbulence. Twenty years later, and the boundary-layer turbulence, coupled with airflow at close to 4 times the speed of the 1930’s, meant severe problems for the B36-XF85 combination. The XF85 could indeed be easily released and launched from the B36. What it could not easily achieve, was being retrieved and being returned aboard the B36; for the reasons outlined above.
I have always been fascinated by the parallels between the two systems, and admired the bravery of the men who flew them; hence my research into the topic.
I hope this explanation suffices to answer your question, My friend.

Kind and Respectful Regards RS*, Uyraell.

[Rising_Sun]

@Uyraell

RS* my friend, the Sparrowhawk is a single seat fighter.
The picture shows the pilot guiding the retrieval hook onto the trapeze, which is then retracted into the airship, bringing the fighter onboard. One of the many unusual characteristics of the Sparrowhawk is that, though a biplane, both mainplanes attach to the fuselage, at top and bottom (spine and keel) respectively. The pilot in effect sat with his head and shoulders above the plane of the top wing.
To the casual viewer, the pilot thus appears as though he might be a secondary crewman ie, observer, and it is easy to assume that presence of a second person who is piloting the aircraft. In fact, there was no space in the fighter for two men, it being that its’ dimensions are little more than a Kingswood stationwagon in either span or length. This was a very small aircraft, indeed, as small as some of the 1930’s air-race airplanes.
The “pick-up hook” is guided on to the trapeze, where it engages with a positive lock, The trapeze then retracts.
This same system was resurrected for the XF85 Goblin and B36 Peacemaker combination in the 1950’s.
However: what was readily accomplished in the 1930’s at speeds of 70 mph was a far different proposition in the 1950’s, at speeds above 250mph. Whereas in the 1930’s there was in effect insufficient speed to concern either airship or fighter, side-gusts notwithstanding, there was next to no airflow-boundary layer turbulence. Twenty years later, and the boundary-layer turbulence, coupled with airflow at close to 4 times the speed of the 1930’s, meant severe problems for the B36-XF85 combination. The XF85 could indeed be easily released and launched from the B36. What it could not easily achieve, was being retrieved and being returned aboard the B36; for the reasons outlined above.
I have always been fascinated by the parallels between the two systems, and admired the bravery of the men who flew them; hence my research into the topic.
I hope this explanation suffices to answer your question, My friend.

Kind and Respectful Regards RS*, Uyraell.

Thanks for that.

I had assumed that it would be pretty difficult to fly the plane in the correct position and hook up with the free hand at the same time, so I assumed an observer was doing it.

It’d be a nice piece of flying.

[Uyraell]

RS*, you are more than welcome, my friend.
I too feel the pilots must have been both skilled, and brave men.
I also feel the retrieval system must , by its’ nature, have required more of those men and their skills than many other more mundane systems.

Kind and Respectful Regards RS*, Uyraell.