Bell Model 48 (H-12/XR-12)

[Cy-27]

I can't find any detailed entry for this on the forum, if there is, I apologise.

I visited Volandia Museum in Malpensa yesterday and there was a sorry-looking exhibit between two buildings marked "Bell 48". Some photos attached. In the third photo the circular item next to the wall of the building is the tail boom assembly.

This was the company designation for the military variant of the Bell Model 42.

Two were built as five-seat XR-12s for the US Army and a production contract for 34 was cancelled in 1947.

Wikipedia has this variant as part of the H-12 family of which a total of about 13 were completed.

The type is also quoted here: http://www.secretprojects.co.uk/forum/index.php/topic,15158.0/all.html

The close up of the placard attached reads:
"Helicopter Bell 48 to be sent Fort Worth (USA) for restoration"

It looks as though it may be next seen the other side of the Atlantic.

 

[Stargazer]

Interesting find!
Yes, definitely headed for the States it seems.
Not knowing where you live or where Malpensia is, I gather from the inscriptions on the sign that it must be in Italy, right?
Anyway, thanks a lot for sharing!

 

[Apophenia]

Interesting find!
Yes, definitely headed for the States it seems.
Not knowing where you live or where Malpensia is, I gather from the inscriptions on the sign that it must be in Italy, right?
Anyway, thanks a lot for sharing!

Interesting indeed! Skyblazer: As you guessed, Malpensa is in Italy near the Swiss border. Volandia Parco e Museo del Volo Malpensa (Park and Museum of Flight, Malpensa) is in Vizzola Ticino in the former Caproni complex.

 

[walter]

Hi gentlemen
Very interesting stuff and nice to see history returning to the country of birth.
You may recall that Agusta developed their AB-102 which was a derivative of the Bell Model 48/H-12.
From my notes I see that Bell sent, in 1957, a model 48A to serve as pattern aircraft for the AB-102. This Model 48A differed mainly from the earlier Model 48 (XR-12/XH-12) in having square cabin windows and a new forward fuselage/nose section, longer rear fuselage and a 4-wheel u/c. I think that finally Bell produced 13 YR-12B/YH-12B aircraft for the USAAF/USAF, which were based on the XR-12B/XR-12H prototype, but with a more powerful 600hp R1340 radial engine.

 

[Stargazer]

XR-12-BE 10-seat prototypes with 540hp P&W R-1340-AN-1 engine (Franklin 6V4 planned but not powerful enough) (2 built) [46-214/215]
YR-12-BE pre-production batch, cancelled and replaced by YR-12B (10 ordered, all cancelled) [46-217/226]
R-12A-BE production 13-seat version with 600 hp Franklin 6V4 engine (34 ordered, all cancelled) [47-491/524]
XR-12B-BE prototype for stretched cabin version with Pratt & Whitney R-1340 Wasp engine [46-216]
YR-12B-BE pre-production batch, also with Pratt & Whitney R-1340 Wasp engine, reusing serials of cancelled YR-12 (10 built) [46-217/226]

So, yes, 13 built altogether.
The XR-12, XR-12B and YR-12B (not used) became the YH-12, XH-12B and YH-12B in the 1948 designation system.
The XR-12 was developed under the supervision of P. Koegler as chief engineer for the project.
Interestingly, the civil register gives two XR-12s as modified Model 30 prototypes but I'm not too sure about that.
A commercial derivative, the Feederliner, was planned but abandoned when the military version received no orders.

First four photos below are of the YR-12, or Model 48.
The others depict the YH-12B, or Model 48A.
You can clearly see the longer airframe, rounded off cockpit and square windows of the latter.
I do not think "YH-12h" was a valid designation designation at any point, and it is not in accordance with DoD usage anyway.
My theory is that it might have been used inhouse by Bell to designate the "hydro" variant of the prototype, but it's only guesswork.

 

[Stargazer]

Also, here's an article from Popular Science (Dec. 1950):

 

[walter]

Hi Skyblazer
Very nice stuff and some photos I had never seen before. Thanks!!
The engine in the XR-12 was, I believe, a 540hp P&W R-1340-AN-1 radial. The Franklin 6V4 engine reported had, AFAIK, not enough power (175hp - 300hp, depending on the sub-model) for such a big heli.

 

[Stargazer]

Hi Skyblazer
Very nice stuff and some photos I had never seen before. Thanks!!
The engine in the XR-12 was, I believe, a 540hp P&W R-1340-AN-1 radial. The Franklin 6V4 engine reported had, AFAIK, not enough power (175hp - 300hp, depending on the sub-model) for such a big heli.

Thanks walter. I've modified my post accordingly.

 

[Stargazer]

I suppose this is almost off-topic, but not quite... The Model 48 itself was a slightly enlarged military development of the sole Model 42 prototype:

 

[Kuno]

...I recall I have seen this wreck some years ago - together with some other helicopter wrecks. It was located outside in the grass, away from the biuldings. Will dig out the photos and post them here.

 

[Stargazer]

...I recall I have seen this wreck some years ago - together with some other helicopter wrecks. It was located outside in the grass, away from the biuldings. Will dig out the photos and post them here.

That would be neat... Thanks a lot in advance!

 

[Petrus]

Here you've got a film on the Bell 48

View: https://www.youtube.com/watch?v=PLURbSWO9OQ

 

[Stargazer]

It was briefly mentioned in another post, but the Bell 48A had a spinoff: the Agusta A.102 — which, contrary to what Wikipedia and others claim, was never called the AB.102 and was never labeled as an "Agusta-Bell" product. It is sad that many people not conversant with a particular subject tend to think that anything found on Wikipedia is gospel truth... and that most online sources on any particular subject are simply Wikipedia copies...

Agusta Helicopters

History of Agusta helicopters

www.helis.com

Agusta-Bell AB.102 - Wikipedia

en.wikipedia.org

Helicopters

First envisioned by Leonardo da Vinci and first deployed in World War II, the helicopter is now a universal icon of modern warfare, a key component of combat planning around the world, and one of the military's most versatile and effective tools.Helicopters: An Illustrated History of Their...

books.google.fr

 

[Cy-27]

I recall I have seen this wreck some years ago - together with some other helicopter wrecks. It was located outside in the grass, away from the biuldings.

I've seen a photo with four helicopters parked alongside one another where Kuno describes. I think there used to be an early Mangusta among them parked away from the buildings - there is a lot of construction work underway near where they used to be - looks like a new road. I suspect the hulks have been moved, they were no where to be seen when I looked last week.

The lined up examples can be seen in this section in the reply from PaulMM (Overscan) near the foot of the page: http://www.secretprojects.co.uk/forum/index.php/topic,869.msg218438.html#msg218438

 

[Petrus]

Take a look at

https://www.heli-archive.ch/en/helicopters/in-depth-articles/agusta-bell-102

It contains info on Agusta-102 in Switzerland (with photos).

 

[P-STICKNEY]

It was briefly mentioned in another post, but the Bell 48A had a spinoff: the Agusta A.102 — which, contrary to what Wikipedia and others claim, was never called the AB.102 and was never labeled as an "Agusta-Bell" product. It is sad that many people not conversant with a particular subject tend to think that anything found on Wikipedia is gospel truth... and that most online sources on any particular subject are simply Wikipedia copies...

http://www.helis.com/timeline/agusta.php
https://en.wikipedia.org/wiki/Agusta-Bell_AB.102
https://books.google.fr/books?id=xLis8p7uLaUC&pg=PA128

I can't speak to Wikipedia's provenance, but U.S. FAA Type Certificate 7h3 is still active, is held by Agusta S.P.A., and names the type as the AB-102.

 

[Stargazer]

I can't speak to Wikipedia's provenance, but U.S. FAA Type Certificate 7h3 is still active, is held by Agusta S.P.A., and names the type as the AB-102.

Oh! Thank you so much for this piece of info!

So there's an interesting twist to the story here... The type was only known as the A.102 in Europe. However, with an active Agusta-Bell collaboration planned if produced, and prospects of possible sales in North America, the designation AB-102 was invented — though of course not used, since no example of the type built wound up in America and only a handful of prototypes existed.

Thanks again P-STICKNEY for bringing this to our attention... and welcome to this forum!

 

[Petrus]

A quite interesting article on the Bell 48 may be found at https://verticalmag.com/features/bell-model-48-helicopter-vertical-rewind/. Below you've got some of pictures that come from the article.

As for the float-equipped variant another two drawings* from a brochure 'Helicopter Model 48 Available for Mass Production' by Bell Aircraft Corporation of March 1951.

Piotr

*My feeling is the picture showing the Bell 48 with floats in flight is actually an artist's impression not a photo. Obviously I may be wrong.

 

[Petrus]

And finally two photos of the Augusta AB-102 from the "Ali Nouve" magazine (Issue 4 of 1959). In the photo of the helicopter's cabin a seating arrangement for two pilots and six passengers may be seen.
For those who read Italian the article on the AB-102 from the above mentioned issue of the "Ali Nuove".

Piotr