Northrop A-9 AX Design Evolution

[overscan (PaulMM)]

Found via google patent search. Northrop design, seems to be related to early stages of AX.

Patent: D218,856
https://patents.google.com/patent/USD218856S/en

 

[Pioneer]

Great find with the Northrop 'early AX design' drawings, Overscan!
Does the Patent info you found have any technical data/specifications ????

Regards
Pioneer

 

[elmayerle]

Found via google patent search. Northrop design, seems to be related to early stages of AX.

Patent: D218,856

Shades of the Learfan!!

 

[JAZZ]

Interesting find ...thought i would have a go at quickly dressing one of the drawings up...prehaps I should post this under-models-art?

 

[overscan (PaulMM)]

Unfortunately, its an "ornamental design" patent and includes little information except it was "made in the course of Contract No. F33657-67-C-100 with the United States Air Force" and filed June 30, 1969.

Nice addition to the drawing, Jazz.

 

[overscan (PaulMM)]

Found a little mention of this here: http://aeroweb.brooklyn.cuny.edu/specs/northrop/ya-9a.htm

I worked at Northrop (now Northrop-Grumman) in the 1980s.
When I visited the March AFB/ARB Air Museum, I finally
got my first chance to see and touch one of the A-9A prototypes.

The most unusual variant of the A-9A proposed was a
desktop 1/48th scale model of a PROPELLOR version of
the A-9A. The propellor arrangement was a PUSHER
configuration, with 3 tail fins arranged in a Y shaped
configuration: 1 ventral fin, 2 angled dorsal fins.

I am not sure what they had in mind with that concept
model - perhaps a slower, Skyraider type attack craft.
I'll probably never know for sure, but the model was
interesting.

So theres a model on display at March AFB Museum? Or is he referring to somewhere else?

 

[Sentinel Chicken]

I think what he's referring to is that one of the actual flying A-9A prototypes is at the March AFB Museum.

 

[lark]

Northrop Corp. produced a flying demonstrator of its
turbo-pusher concept.

A photo is shown on page 26 of Aviation Week & Space Techno
of September 23 , 1968.

 

[overscan (PaulMM)]

Could you elaborate a little? What exactly is this demonstrator?

 

[Matej]

I think it was aerodynamic and configuration testbed. I have some pics, will search for them.

 

[lark]

Illustration shows a little pusher aircraft with fixed 3 wheel undercariage.
3th wheel in the lower tailfin.

Pusher prop at the extreme tail end.

Overall configuration is close to the drawings already shown
but plane looks no so big.

'Northrop Turbo pusher' written on the side of the aircraft.

 

[Matej]

Here:

 

[amsci99]

Matej,

This looks like the Sierra Sue and there is an article on it in Air Enthusiast. The link is at
http://shop.keypublishing.com/acatalog/Air_Enthusiast_issue_116.html

 

[Matej]

Great find. Do you have also some short extract from that article?

 

[amsci99]

Matej,

Unfortunately not. I am trying to track down a used copy on eBay.

 

[overscan (PaulMM)]

http://airpower.callihan.cc/HTML/Spotlight/SierraSue.htm
http://web.mit.edu/asfalcon/www/Images/LAX Photos/2006_07_01_1/IMG_0652.JPG
Some pictures - its at the Western Museum of Flight.

The Southern California Historical
Aviation Foundation (SCHAF) has
proudly announced the arrival of
"Sierra Sue" at their Western Museum of
Flight in Hawthorne, California, where
it will be on display for an undetermined
period of time. A unique "pusher"
aircraft with a single propeller in
back of its tail, Sierra Sue was designed
and built in the 1950s as a race plane
by engineers at North American and
Northrop in their spare time. In the
late 1960s, it served as a concept
demonstrator in developing a prototype
attack aircraft for the U.S.Air Force, but
the design was dropped when the Air
Force announced its requirement for a
jet, rather than a propeller aircraft.

 

[Antonio]

Thanks for the pics, Paul

In this photo, we can see the AX concept illustrated in the papers in front of the aircraft.

 

[overscan (PaulMM)]

Unfortunately the Western Museum of Flight had to move and I'm not sure of the current status at its new site. If anyone is in the area, maybe they could visit and photograph the pics on the placard?

;D

 

[hesham]

Hi,

when I search about Douglas aircraft I find that
design for Northrop,I think it was COIN aircraft,
I don't remember if we spoke about it before or not.

https://patents.google.com/patent/USD218858S/en

 

[overscan (PaulMM)]

Added Hesham's second Northrop patent. Clearly a variant of the previous design.

https://patents.google.com/patent/USD218858S/en

 

[overscan (PaulMM)]

https://patents.google.com/patent/USD229353S/en
Northrop A-9 patent. Just to confirm that the previous studies are AX studies, Walter E. Fellers is the first designer named on all three designs.

 

[jackehammond]

Dear Members,

Did the Northrop YA-9A have any advantages over the Fairchild YA-10A design?

Jack E. Hammond

 

[flateric]

Some good thoughts here
http://aeroweb.brooklyn.cuny.edu/specs/northrop/ya-9a.htm

 

[overscan (PaulMM)]

A-9 patents, for completeness.

 

[overscan (PaulMM)]

Interesting A-9 images

Sources:

Northrop: An Aeronautical History
http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=3198

 

[overscan (PaulMM)]

More

 

[overscan (PaulMM)]

More

 

[overscan (PaulMM)]

Nice comparison shot

 

[Maveric]

Do you know the Company designation for the A.9? N... ?

 

[Abraham Gubler]

The Northrop AX design appears to align with the Northrop pusher aircraft patent. There was another patent of a very similar aircraft. Perhaps the second design (forward cockpit, pictured bellow) lacks the 30mm Avenger and is a more conventional COIN aircraft design?

 

[overscan (PaulMM)]

Indeed - both patents were already posted in this topic

 

[Abraham Gubler]

Indeed - both patents were already posted in this topic

That's where I found them! But I couldn't understand why two pusher designs of very similar aerodynamic configuration at the same time? At first I thought the forward cockpit design might be a larger more powerful aircraft?

The picture and data of the Northrop pusher shows from the A-10 study shows where the 30mm Avenger gun and ammo and the engines would be located. The difference between this pusher and the other pusher would appear to be the later central mounted engines and forward cockpit. Indicating the removal of the Avenger gun system and reconfiguration of the weights in the fuselage to compensate.

 

[overscan (PaulMM)]

Yes, that is possible.

D218856 - filed June 30th 1969 - mentions it was designed under the USAF AX study contract.
D218858 - filed June 30th 1969 - no mention of contract

Both designs were filed almost 2 years after the studies. It is therefore possible the second design is a later development.

 

[overscan (PaulMM)]

Found a tiny image of the Northrop pusher design on WMOF website.

http://www.wmof.com/Serria Sue.html

 

[Skybolt]

Maybe these help... B)

 

[Abraham Gubler]

Well its clear from Skybolt's drawing that both Northrop pusher patents are AX aircraft armed with the 30mm Avenger. It would appear they just refined the design.

 

[overscan (PaulMM)]

YA-9A walkaround by forum member Bill Spidle.

http://www.primeportal.net/hangar/bill_spidle/ya-9a_walk_1.htm

 

[Triton]

Cutaway drawing of Northrop Y-9A.

Source: http://sobchak.wordpress.com/2009/10/19/gallery-northrop-ya-9/

 

[overscan (PaulMM)]

1967 Northrop AX model tested in NASA 7 X 10-Foot High Speed Tunnel.

Unfortunately, a poor scan.

http://crgis.ndc.nasa.gov/mw/images...ox_Close_Air_Support_(A-X)_Airplane_Model.pdf


[Photos removed - better versions below - Admin]

 

[Stargazer]

Evaluation of the Acme Sierra as the Northrop Turbo-Pusher in the same period seems to make more sense suddenly...