A hastily arranged crew portrait taken yesterday at the Kennedy Space Center shows new command module pilot John L. Swigert (left), mission commander James A. Lovell, Jr. (centre) and lunar module pilot Fred W. Haise, Jr. Photo: NASA/KSC

Apollo 13 is now expected to be launched tomorrow with Astronaut Jack Swigert, the backup Command Pilot, in the centre couch. This was announced at Cape Kennedy a few moments ago after the flight had been on the verge of postponement for nearly a week because the original Command Pilot, Ken Mattingly, having mixed with children developing German measles, might develop it himself during the flight.

The decision to go ahead after switching a single crew member -- never done before in the whole of America's space programme -- was made by Dr Thomas Paine, head of the space agency NASA. For three days Swigert has been sweating it out in the simulator with Apollo 13's commander, Jim Lovell, and the other crew member, Fred Haise, trying to convince critical flight controllers, as well as his fellow astronauts, that in a crisis he could work with them just as well as Mattingly would have done after two years of intensive training.

Thomas K. Mattingly, Apollo 13's original command module pilot, was bumped from the mission because he was exposed to the measles. Photo: NASA/JSC

Swigert is a big man, sixty pounds heavier than Mattingly; and much nimble twisting and turning is required from him to manipulate switches.

Lovell himself, earlier in the week, favoured postponing the mission. Swigert, despite being the man who wrote the astronauts' text book on what action to take in any conceivable difficulty, had a tough job persuading Lovell, veteran of three previous flights, with a total of 570 hours in space, to change his mind. But he succeeded.

At Houston a new plaque is being prepared, giving the corrected names of the crew, and will be flown to the Cape so that it can be left on the moon.

So lift-off of Apollo 13 is now scheduled for 1313 hours Houston time. Jim Lovell's wife, Marilyn, has been asked if this worries her, and says she's not a bit concerned.