Morse Code Flag for the Letter X - X-Ray : _ . . _

The Morse Code Flag for the letter X has two stripes and two stars.  The order is reflective of the specific code for X which is related to DOTS and DASHES.  Since Morse Code Flags are always read downwards, it clearly spells out DASH, DOT, DOT, DASH, which is the letter X in Morse Code. 

The flag has a green background because the letter X is the 24th letter of the alphabet.  The number 4 is coded to green, because, green is the 4th colour of the rainbow/spectrum. Yellow is included because yellow is the contrast minority-indicator for a green background/field.  Also note that the tens place value for twenty-four is ignored.   Only the ones place value is used to set the main colour of the background, which for the letter X is 4, that is coded to green. Thus we have a dominantly green flag for the letter X in Morse Code. 

Morse Code Flag for the Letter W - Whiskey

The Morse Code Flag for the 23rd letter of the alphabet has a yellow background.  The reason being is that 3 is coded to the colour yellow.  The tens column number of 2 from 23 is ignored.  The star and stripes are blue because blue is the assigned contrast indicator for yellow. Additionally the stars and stripes are coded to DOTS and DASHES, which in this case reflects Morse Code for the letter W.

Morse Code Flag for the Letter V - Victor . . . _

The Morse Code Flag for the letter V has three stars, one stripe, and an orange background.  Morse Code Flags have the DOTS and DASHES coded to Stars and Stripes.  Thus this flag when read downwards reads the letter V in code.  It has an orange background because V is the 22nd letter in the alphabet.  The number 2 is coded to orange.

Coincidentally the Morse Code V flag is nearly a perfect invert of the Morse Code B Flag, the stars are below on B while above on V.  How strange?  This closeness is also reflected in the keyboard, whereby V and B are next to each other, and often lead to typos.  Additionally many non-native speakers of English easily get these two sounds confused.  And even if you are a native English speaker, the first time one speaks to new individual who says V or B, it is very easy to confuse. 

Morse Code Flag for the Letter U - Uniform

The Morse Code Flag for the letter U has a red background, two white stars, and one white stripe.  The stars represent DOTS while the Stripe represents a DASH, in Morse Code.  As these types of flag are always read downwards it reflects the nature of the letter U.  The flag is red, because this colour is coded to the number 1.  As the letter U is the 21st letter of the alphabet, we have a red flag.  Also note the numeral 2 from 21 is ignored, since Morse Code flags only use the ones place value to calibrate the colour.

Morse Code Flag for the Letter T - Tango _

The Morse Code Flag for the letter T is a simple white flag with one black stripe.  The one stripe is reflective of the one DASH for the letter T or Tango.  The flag is white because T is the 20th letter, with zero in the ones place digit, which is calibrated to white.

Morse Code Flag for the Letter S - Sierra . . .

The Morse Code Flag for the Letter S has a pink background.  Reason being, the letter S is the 19th letter of the alphabet.  And the number in the ones value is calibrated to the order; and 9 is coded to pink.  The three stars represent aDOTS, and are blue because blue is the contrast indicator for pink.

Morse Code Flag for the Letter R - Romeo . _ .

The Flag for the letter R is black and white.  The stars represent DOTS while the Stripe represents a DASH.  The black background is coded to the number eight.  We have a black flag because R is the 18th letter.  Morse Code Flag background colour is based upon the ones digit value, as the tens digit value is ignored.