Just got promoted to Senior Airman (E4).

Seems quick to me.  He graduated BMT in Feb of 2015.

Up to Senior Airmen it's all automatic, time in grade promotion = if you have self control and stay out of trouble you get promoted in X# of months.

Kinda like "Oh, you're still here?  It's been X# of months so here's another stripe."

Exception: If they get below the zone promotion, then they get promoted early.

Congrats to your nephew.

As for it being quick, depends on what his AFSC (really tech school graduation date) is, and how long his initial enlist is.  

Per AFI 36-2502:
Airmen (fully qualified) are promoted to SrA upon meeting minimum requirements in Table 2.1, when recommended by the promotion authority in writing, and have completed 36 months TIS and 20 months TIG or 28 months TIG (whichever occurs first)

Loadmaster on a C130

I believe that tech school is only about a month long.  If they are still doing things they way they did back when I enlisted, if you did 6 years on your initial contract, you automatically got promoted to E-3 upon graduation, E-2 if it was 4 years.  As such that would put him "roughly" in that 28 month category.

I went in as an E3 because of my college credits, but my recruiter kept pushing me to sign 6yr contract, with E3 as an incentive.

Far from it.  

Any Career Enlisted Aviator job has a long pipeline.  BLM may be only 30ish training days, but the FTU for the airframe where he actually learns to perform load duties is several months long.  Some airframes (like the HC-130) even require a second FTU before he gets to his first unit and starts MQT.  

BMT
EAUC  (1-level awarding course)
BLM    (3-level awarding course)
S-V80-A
S-V86-A
IQT at the FTU   (basic aircraft qualification)
MQT at first assignment   (basic mission capable)
Then start CDCs and upgrade training

Most Loads will spend about a year in the pipeline from BMT to MQT due to course lengths and scheduled start dates.

We called it "below the desk" promotion.





The Ol' Crew Chief