RATO used to get civilian aircraft out of airports with inadequate runway length? There are plenty of stories of large aircraft accidentally, or emergently, landing at airports that don't meet the plane's runway length requirements.  The only solution to getting them out that I've read is stripping them to the point that some authority deems them light enough for takeoff on the short runway.

What I haven't read of are the use of any measures to increase the thrust available for the takeoff run.  The first idea that came to mind was the use of RATO.  Is this possible with civilian aircraft?  Is it done?  If not, why not?

(My second thought was to temporarily install water injection.  But then I figured that by the time a system like that could be tested and approved the plane could have been disassembled for overland shipping.)
The DH Comet was equipped with RATO.

The Fairchild SA226 had a RATO bottle in the tail to improve single engine performance.  As I recall, removing the spades on the main landing gear eliminated enough drag to render the RATO unnecessary.

Boeing built twelve "727-200/JATO" variants for use by Mexicana Airlines.



  The rocket installation was intended for emergency use only when
  flying out of a hot and high airport at maximum gross weight. Without
  the JATO, the aircraft would have to be payload restricted to account
  for the need to reach a safe altitude in the event of an engine loss
  after committing to takeoff. By having the JATO provision, Mexicana
  could operate its 727-200s at full payload. In the event of a loss of
  engine at past V1, the JATO unit would fire and allow the
  heavily-laden jet to reach a safe altitude and get aerodynamically
  cleaned up.


This old video shows a demonstration of that scenario with one of those special 727-200s:

                
            


  The JATO provision was eventually made obsolete by later developments
  in the JT8D engine that featured "APR" automatic power reserve. It
  sensed a power decrease from one of the engines failing on takeoff and
  automatically boosted the power to the remaining two engines by a
  significant margin.