MACO ranks
The rank system used by the United Earth MACO military force of 22nd century, and the Terran Empire in the mirror universe, are structured similarly to historic US Army, US Navy and US Marine Corps ranks.

General 
The flag officer rank of general was used by General , commanding officer of the MACOs who were assigned to the . This rank was approximately equivalent to an Starfleet admiral. ()

Major 

The rank of major was used by MACO field officers commanding a squad of soldiers on special assignments. The insignia was a gold oak leaf on a yellow shoulder patch.

Major J. Hayes commanded the MACOs aboard Enterprise. Traditionally, a major was equivalent of a naval lieutenant commander. However, Starfleet had no such rank at the time. Though Hayes may have technically outranked Lieutenant Malcolm Reed, the MACO team was still subordinate to the ship's chief of security. ()

In the mirror universe, Major  was the chief of security aboard the . ()

Sergeant 

The sergeant insignia consisted of three white chevrons on a blue shoulder patch. ()

N. Kemper
 (mirror universe)
B. Moreno

Corporal 

The corporal insignia consisted of two white chevrons on a blue shoulder patch.

Several corporals were seen assigned to Enterprise. ()

 
 
 
 
 
 
 O'Malley
 
 
 
  (mirror universe)

Private 

The private insignia consisted of a single white chevron on a blue shoulder patch. ()
 R. Azar
 C. Black
  (mirror universe)
  (mirror universe)
 Carender
 E. Hamboyan
  (mirror universe)
 S. Money
 N. Myers
 T. Palmer
 
 
  (mirror universe)
 W. Woods
  (mirror universe)

Appendices

Background information 
Most of the MACO rank insignia designs seem to be inspired by the ranks of the United States Marine Corps, such as the oak leaf on the major insignia.

A chart of MACO rank insignia featured in , also introduced the ranks of brigadier general, major general, and lieutenant general, though these were not mentioned on screen.

A complete set of MACO rank insignia patches was sold as part of the It's A Wrap! sale and auction.

External link 
 

de:MACO-Ränge
es:Rangos MACO