Evolution of the Eurofighter Typhoon: TKF-90, AST 396, AST.403 and more

[red admiral]

But the irony, the EAP is based on the ACA’s aerodynamic design correct? And the RAF did run with it.

There are many changes when you look at it, many of them directly addressing the points raised in the RAE memo; e.g. move to long coupled canard to reduce drag in supersonic flight and removing post stall manoeuvre. The ventral intake on both TKF-90 and EAP/Typhoon masks a lot of the other aerodynamic differences.

 

[overscan (PaulMM)]

There are many changes when you look at it, many of them directly addressing the points raised in the RAE memo; e.g. move to long coupled canard to reduce drag in supersonic flight and removing post stall manoeuvre. The ventral intake on both TKF-90 and EAP/Typhoon masks a lot of the other aerodynamic differences.

The RAE are arguing for Rafale and P.110-style short-coupled canards in the memo and objecting to the forward TKF-90 position that ACA, EAP and Typhoon share.

 

[F-2]

From Eap: Britain’s Last manned demonstrator

It seems P.110 would have excellent turn performance.

 

[red admiral]

The RAE are arguing for Rafale and P.110-style short-coupled canards in the memo and objecting to the forward TKF-90 position that ACA, EAP and Typhoon share.

They are at that point which is interesting; all about trying to maximise that high subsonic sustained turn performance

There quite some differences (size, position) between the TKF-90 canard and that for EAP and Typhoon (and other forebody vortex generating strakes), which reflect on the difference usage intended - i.e. high AoA pitch recovery post stall for TKF-90

Whats then missing is info on cg location / level of pitch instability, which has a major impact on the aerodynamic characteristics

 

[TsrJoe]

Marconi promotional artwork, Flight International, June 1987

 

[F-2]

From Designing for Stealth in Fighter Aircraft (Stealth from the Aircraft Designer's Viewpoint)
Ray Whitford

 

[TsrJoe]

Flight International, 31 December 1983 (EAP. original design to P.110/ACA. configuration)

 

[hesham]

From an MBB report on a 1977 wind tunnel model test of high AOA / post stall capability.

1) delta wing
2) delta wing with wingerons and fins below the wing
3) trapezoidal wing with tail
4) delta wing with canard
5) trapezoidal wing with tail and vented fins

Conclusion was in favour of delta wing with canard (unsurprisingly).

Source:
High Angle of Attack Aerodynamics AGARD-CP-247

http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA067323&Location=U2&doc=GetTRDoc.pdf

[Added better copies of photos - Administrator]

Here is a bigger views,from this book.

 

[hesham]

According to Henry Matthews (Prelude to Eurofighter) this is BAe's P.120 fighter derived from EAP. I've seen it described as Eurofighter EFA too though.

From Flight 1986,

we still love this stuff.