Veteran Liberal MP Bronwyn Bishop has bid farewell to Federal Parliament with a pointed reference to the travel expenses scandal that ended her tenure as speaker.

Mrs Bishop's 29-year political career has come to an end after losing a bruising pre-selection battle for her Sydney seat of Mackellar.

She has served in both houses of parliament, was a junior minister in the Howard government and speaker in the Abbott government, but was forced to resign from that position last year after sustained pressure over her use of travel entitlements.

In her valedictory speech, Mrs Bishop revealed she was asked to stand down to protect the then prime minister, Tony Abbott, whose leadership was under threat.

"I was asked to resign for Tony Abbott, someone whom I had assisted and worked with and respected for many years," she said.

"There is much more than meets the eye in that saga but not for now."

Mrs Bishop's career as speaker began to unravel after it was revealed she had charged taxpayers $5,000 to charter a helicopter from Melbourne to Geelong for a Liberal Party fundraiser.

She initially defended her use of entitlements but after weeks of pressure, was forced to apologise and then stand down.

In her book, The Road to Ruin, political commentator Niki Savva said it was Mr Abbott's office that told Mrs Bishop to hold firm and not apologise, even though she had wanted to.

'Paul Keating just called you a fire cracker'

Mrs Bishop took an early liking to aviation as the minister for defence materiel, drawing laughs from the chamber, when she recalled a story about flying an F-111 fighter jet.

"We did a mock bombing raid, which was lots of fun, we went in low, dropped our pay load, barrel rolled," she said.

Tony Abbott with Bronwyn Bishop in 2012. ( AAP: Alan Porritt )

"We then came up and the pilot said to me 'would you like a go?' and I said 'would I what!' and so he let me take it.

"We went back, came in for another raid and pulling 4.5 G's, I did the roll and it was just fantastic."

She spoke fondly of her early years in Parliament as a Senate backbencher, where she pioneered an aggressive form of questioning during estimates hearings, as well as her move to the House of Representatives, which was greeted with friendly-fire from the then prime minister Paul Keating.

"I was opening something and somebody bowled up and said 'Paul Keating has just called you a fire cracker ... he called you a Catherine wheel, you just roll and roll and roll'.

"I said 'Really? Well perhaps all I can say is Mr Keating reminds me of a sparkler; all froth and fire and then it goes out and all that's left is a thin black stick'."

After her speech, Ms Bishop was applauded and embraced by dozens of Liberal MPs, but Mr Abbott was absent from the chamber.