Sir Philip, who left Mowlem in 1995, has been a non-executive director of Railtrack since the same year and succeeds Sir Robert Horton.
A Cambridge-educated engineer, Sir Philip became chairman of Mowlem in 1979 and oversaw a series of ups and downs for the contractor.
He was instrumental in the development and construction of London’s loss-making City Airport, and was head of Mowlem when it hit trouble on the west London Carlton Gate housing scheme. It eventually lost £14m in court over the project.
But he also ran the company when it made hundreds of millions from the 1980s development boom, and he was involved with the construction of the Falkland Islands airport in 1983.
Sir Robert said: “Sir Philip’s great experience of the construction industry will be valuable in steering Railtrack through the next phase of development.
“The company faces a challenging agenda and we are fortunate that the new chairman is a very experienced senior industrialist who brings the added bonus of having served on our board since 1995.” Sir Philip said he was looking forward to working with Railtrack management to bring about promised improvements in service.