Routine codes 0000: o military intercept code (in the US) o mode C or other SSR failure (in the UK). o shall not be used is a non-discrete modecode (!urope) 000": #ilitary code for hi$h speed uncontrolled (non-%C directed) fli$ht (US) 00&&: 'arachute droppin$ in pro$ress (UK) "000: o (nstrument )li$ht Rules (()R) fli$ht belo* "+,000- *hen no other code hasbeen assi$ned (Canada) o non-discrete modecode reser.ed for future use in #ode S radar en.ironment *here the aircraft identification *ill be used to correlate the fli$ht plan instead of the modecode "/00: 0isual fli$ht rules (0)R) fli$ht, this is the standard s1ua*2 code used in ustralian and 3orth merican airspace *hen no other has been assi$ned. "400: 0)R fli$ht abo.e "/,500-S6 *hen no other code has been assi$ned (Canada) /000: %he code to be s1ua*2ed *hen enterin$ a secondary sur.eillance radar (SSR) area from a non-SSR area (used as Uncontrolled ()R fli$ht s1ua*2 code in (C7 countries and in Canada for uncontrolled ()R at or abo.e "+,000-) 4000: ircraft on a 0)R #ilitary %rainin$ Route or re1uirin$ fre1uent or rapid chan$es in altitude (US) 4400 to 4488: Reser.ed for use by SR-8", 9)-"/, U-/ and :-58, pressure suit fli$hts, and aircraft operations abo.e )6;00 (US only). 4;00: (ntentional 7C) or erobatic )li$ht (US)< 8000: o 0)R standard s1ua*2 code *hen no other code has been assi$ned ((C7)o UK: this code does not imply 0)R= 8000 is used as a $eneral conspicuity s1ua*2.) 800": o Sudden military climb out from lo*-le.el operations (UK) o Used in some countries to identify 0)R traffic ()rance, ...) 8004: erobatic and display code in some countries. 80"0: 0)R circuit traffic code in the UK 808>: 'aradrop acti.ities in )rance (8080, 808", 808/...) 8888: o military interception (US) ("Under no circumstances should a pilot of a civil aircraft operate the transponder on Code 7777. This code is reservedfor military interceptor operations.") o non-discrete code used by fi?ed test transponders (R:#s) to chec2 correctness of radar stations (:(%!). (US, @ermany, 3etherlands, :el$ium, ...) (n :el$ium follo*in$ codes are assi$ned for 0)R traffic under )li$ht (nformation Ser.ices (:>6 )(C) series from 004" till 0058 (n @ermany the follo*in$ codes ha.e been used: 00/": 0)R s1ua*2 code for @erman airspace (5000 feet and belo*) 00//: 0)R s1ua*2 code for @erman airspace (abo.e 5000 feet) s from "5 #arch /008 these ha.e been replaced by the international 8000 code for 0)Rtraffic. Emergency codes 8500: Unla*ful (nterference (AiBac2) 8;00: 6ost Communications 8800: @eneral !mer$ency