Select CSV columns in Powershell where header name contains a specific string

I have a data file of about 10-15 columns from which I want to extract specific columns. Some of the columns I know the exact column header and others I only know that the first two letters will always be "FC". How do I select only the columns where I know the column header and those that start with "FC"? Starting with just the "FC" columns, I have tried like this:

$myCSV = Import-CSV "mydata.txt" -Delimiter "`t"
$FCcols = $myCSV[0].psobject.Properties | foreach { $_.Name } | Where {$_ -match "FC"}
$myCSV | select $FCcols

But I just get an error:

Select-Object : Cannot convert System.Management.Automation.PSObject to one of 
the following types {System.String, System.Management.Automation.ScriptBlock}.
At line:3 char:16
+ $myCSV | select <<<<  $FCcols
    + CategoryInfo          : InvalidArgument: (:) [Select-Object], NotSupport 
   edException
    + FullyQualifiedErrorId : DictionaryKeyUnknownType,Microsoft.PowerShell.Co 
   mmands.SelectObjectCommand

Then, if I try:

$myCSV = Import-CSV "mydata.txt" -Delimiter "`t"
$FCcols = [System.Collections.ArrayList]@()
$myCSV[0].psobject.Properties | foreach { $_.Name } | Where {$_ -match "FC"} | %{$FCcols.Add($_)}
$myCSV | select $FCcols

I get the output I want except that it is in "column header : value" format, like this:

FC1839 : 0
FC1842 : 1
FC1843 : 6
FC1844 : 12
FC1845 : 4

FC1839 : 0
FC1842 : 0
FC1843 : 19
FC1844 : 22
FC1845 : 14

I am probably just missing something simple, but how do I get to the point that I am able to select these matching columns and then output them to another .txt file (without the header : value format)?