From the TTA Facebook group:
It looks like we are going to be launching a Kickstarter for the 40th Anniversary reprint of Spacecraft 2000-2100 AD, sometime in May. This will be a straight reprint using the original art and text. Mr. Cowley has said that if the reprints are successful then he’s interested in doing a brand new TTA Handbook. More information as it becomes available
Yeah, new books if this one works. Start saving your pennies, folks.