Skills in CT are the things your character excels at and could get hired to do.
The skill list is a list of particular types of expertise that might help the PCs along on their adventures.
None of the skills are required to attain desired goals. If you don't have a pilot, then you can find someone who can pilot and hire them, or buy a ticket, or steal a ticket, or hijack a ship, or whatever.... coming up with solutions to roadblocks is a big part of the game.
CT is a pre-Runequest game. Unlike Runequest (as an example) the skill list is not a complete list of what PCs can do, and the skill list on a PC character sheet does not define or limit what the PC can do. PCs not only can use several skills on the skill list ever without expertise (with rules as written) but can do countless actions and activities to move forward toward their goals.
Like Original Dungeons & Dragons the game assumes the Players will come up with actions and activities to,solve problems outside the scope of the limited rules in the text. (The 1977 rules text makes it explicit the skills are there as examples and do not cover all aspects of actions the PCs might choose to take.)
Starting around 1980 the expectations of what skills are in an RPG shifted. Skills lists are there to be comprehensive and to offload the need of the Referee to adjudicate situations outside the printed rules, and instead run all actions of the PCs through the rules text.
Many people coming to the CT rules post 1980-ish found them confusing -- because the expectation or what skills mean and are there to do in RPGs. But the fact is, the CT rules as written, if applied and used as originally written, work fine.
So... short version: A PC with only a few "Skills" on his character sheet is fine. That lists his expertise, but is not a full list of what he can do or try to do.