Saab J-21 Ideas and Inspiration

[GTX_Admin]

A place for your Saab J-21 Ideas and Inspiration

[GTX_Admin]

This is an interesting bird.

It came in both piston:



and jet versions:



It was also fitted with an ejection seat:

[GTX_Admin]

Line drawings for the profilers here:

[GTX_Admin]

The proposed SAAB J-21B. This was a to be a post-war upgraded variant, with a Rolls-Royce Griffon or Packard Merlin inline engine, a pressurised cockpit, heavier armament and a bubble canopy,  It was however overtaken by the jet J-21R development. 




Initially SAAB wanted a DB 605E engine for the J-21B but with the collapse of the 3rd Reich this was not an option.  Alternatively, they redesigned to accept the Packard Merlin.  This however had a lower speed of rotation of the propeller and thus needed a larger diameter prop with the resulting tailboom interference problems.  Preliminary contact was made with Rolls-Royce to investigate changing either the gearing of the Merlin or to fit a 5 bladed prop of smaller diameter.  Eventually however, it was decided that the Merlin installation was too costly and complicated for marginal increase in performance.  This led to the project proceeding along two lines:

1.  The existing DB605B engine but with 100 Octane fuel and some minor modifications (?) was able to get almost the same power as the Merlin; and
2.  The J-21R jet version, initially with home-grown STAL turbojet and eventually with the de Havilland Goblin turbojet.

[dogsbody]

The proposed SAAB J-21B. This was a to be a post-war upgraded variant, with a Rolls-Royce Griffon or Packard Merlin inline engine, a pressurised cockpit, heavier armament and a bubble canopy,  It was however overtaken by the jet J-21R development. 




Initially SAAB wanted a DB 605E engine for the J-21B but with the collapse of the 3rd Reich this was not an option.  Alternatively, they redesigned to accept the Packard Merlin.  This however had a lower speed of rotation of the propeller and thus needed a larger diameter prop with the resulting tailboom interference problems.  Preliminary contact was made with Rolls-Royce to investigate changing either the gearing of the Merlin or to fit a 5 bladed prop of smaller diameter.  Eventually however, it was decided that the Merlin installation was too costly and complicated for marginal increase in performance.  This led to the project proceeding along two lines:

1.  The existing DB605B engine but with 100 Octane fuel and some minor modifications (?) was able to get almost the same power as the Merlin; and
2.  The J-21R jet version, initially with home-grown STAL turbojet and eventually with the de Havilland Goblin turbojet.

What about fitting a counter-rotating prop as per an Avro Shackleton?


Chris

[finsrin]

"Counter-rotating prop as per an Avro Shackleton" - Nice :)
I sense a speed increase.

[perttime]

The line drawings look like the ones Wikimedia tends to have... Yep, there's SVG files there, so you can get good scalable images
https://commons.wikimedia.org/wiki/File:Saab_J-21.svg
https://commons.wikimedia.org/wiki/File:Saab_J-21R.svg

[elmayerle]

How about J-21RS and A-21RS in Finnish service, possibly with Soviet VK-1 engines replacing the RM2/DeHavilland Ghost engnes?

[perttime]

How about J-21RS and A-21RS in Finnish service, possibly with Soviet VK-1 engines replacing the RM2/DeHavilland Ghost engnes?

J-21R fits in the same time frame as the Finnish acquisition of D.H. Vampire, with Goblin engines. I'm sure any Finnish J-21R would have used the original powerplant.

[GTX_Admin]

Some simple ideas:

[elmayerle]

How about J-21RS and A-21RS in Finnish service, possibly with Soviet VK-1 engines replacing the RM2/DeHavilland Ghost engnes?

J-21R fits in the same time frame as the Finnish acquisition of D.H. Vampire, with Goblin engines. I'm sure any Finnish J-21R would have used the original powerplant.

Correcton accepted.  I had not known that Finnland flew Vampires.  In ihich case, then J-21R/Q21R aircraft with the original engines makes a lot of sense.