to sing the lead. The song is one of only three songs by Pink Floyd not sung by one of their permanent members (the others being "The Great Gig in the Sky" and "Hey, Hey, Rise Up!"). David Gilmour returned the favour by appearing on HQ, along with Harper's occasional backing band, 'Trigger' (Chris Spedding, Dave Cochran, Bill Bruford and John Paul Jones). The single "When an Old Cricketer Leaves the Crease", taken from HQ, is one of Harper's best known songs. Harper also co-wrote the song "Short and Sweet" with Gilmour for Gilmour's first solo record, David Gilmour (released in 1978), and the song subsequently appeared on his own album The Unknown Soldier (released in 1980). Controversy followed the release of 1977's Bullinamingvase. The owners of Watford Gap service station objected to criticism of their food – "Watford Gap, Watford Gap/A plate of grease and a load of crap..." – in the lyrics of the song "Watford Gap", as did an EMI board member who was also a non-executive director of Blue Boar (the owners of the service station). Harper was forced to drop it from future UK copies of the album, though it remained on the US LP and reappeared on a later CD reissues. The album also featured the song "One of Those Days in England", with backing vocals by Paul McCartney and Linda; the single from the album went to number 42 in the UK charts. During this period, Harper's band were renamed 'Chips' and included Andy Roberts, Dave Lawson, Henry McCullough, John Halsey and Dave Cochran. In April 1978, Harper began writing lyrics for the next Led Zeppelin album with Jimmy Page, but the project was shelved when lead singer Robert Plant returned from a break after the death of his son, Karac Pendragon. Following the success of Bullinamingvase, Harper was asked "to write another record quickly". Demo recordings with Harper's newly formed backing band 'Black Sheep' (Andy Roberts, Dave Lawson, Henry McCullough, John Halsey and Dave Cochran, a.k.a. Dave C. Drill) were made, but Harper felt them to be rushed. The record company, who "were in the first stages of a collapse in sales", were not interested in the recordings, nor were they prepared to provide studio time when requested, telling Harper to come back in six months. As a result, Harper withheld the publishing rights to that which had been recorded; an album