[Warwick]

Hi,
I can corroborate this info: Air International May 1994 article by Paul Jackson. "Still nowhere to be seen, even in early 1994, are the promised ADEN 25mm cannon.
Empty under-fuselage cannon pods are worn, as they trap the air, giving improved lift during jetborne manoeuvring. A cone-shaped plug replaces the cannon barrel which would protrude noticeably if fitted."
I have never seen a photo of a GR.7 with protruding barrels.

Air Int. Oct 2002 article by Roy Braybrook: "The 25mm Royal Ordnance Aden 25 was earlier scheduled to arm the BAE Systems Hawk 200 and Harrier GR.5/7, and it was considered as a possible retrofit for the RAF SEPECAT Jaguar, but only 101 examples of this gun were ever produced, and these are now in storage."...."Ground firings of the Aden 25 began in 1983, followed by air firings from a Harrier GR.3 trials aircraft in 1985. on this basis MoD funded full-scale development, and in 1987 awarded Royal Ordnance a production contract for 81 guns. The first Aden 25s were delivered for use on the GR.5 in 1990,
but the RAF found difficulty in achieving an acceptable gun life. The role of prime contractor was then switched to AEI, which solved the basic gun faults- but then feed problems arose when the Aden was installed in the Harrier gunpod. The company was nonetheless contracted to manufacture a further 75 guns, but only 20 of these were delivered before the contract was cancelled on the grounds that the Harrier GR.7 had no operational role that required the use of automatic weapons.
This decision was taken in spite of USMC AV-8Bs having expended thousands of GAU-12/U rounds in Desert Storm,..."

Air Int. Oct 2004 article by Anthony G. Williams: "The RAF was embarrassed during operations against insurgents in Sierra Leone in 2000 to find that it had no suitable weapon for its (gunless) BAE Systems Harrier GR.7s to attack small groups of rebels operating close to innocent civilians."

The GR.9 has a different shape of gunpod (strake)? However I have not found anything in print so far to definetely say that it too is gunless.

HTH, Regards,
Warwick