the earth s rotation  which are approximately 30 m/s RMS deviation in 60 days.  The

system is designed to produce users accuracies of 10 m, 0.01 m/s and 20 ns.   The

additional systems will increase the satellite weight to 2000 kgs. 

The onboard clock is the most critical element of the satellite.  GLONASS clocks of

have seen a steady improvement in frequency and temperature stability from initially

5.10

 11

, to better than 1.10

 13

 with operational lifetimes extending from 5000 to 18000

hrs.  Future plans for GLONASS M may include a Hydrogen Maser with a stability of

5.10

 14

.  Use of the H maser is predicted to increase the operational accuracy of the

system by an order of magnitude.  An experiment is being conducted with Germany and

Switzerland scheduled for a launch in 1995. Further development are planned before

the H maser are installed on GLONASS M satellites in the 2000 + timeframe. 

A.8   SATELLITE LAUNCH PROGRAM

The first GLONASS launch was announced in October 1982, although none of the

three satellites became operational.  GLONASS satellites are launched three at a time

into the same orbit plane by the Proton launch vehicle.  Initially successful launches

were announcement within a day or two in Pravda, but recently the Russians have

provided advanced  notice of launches which have proved accurate to within a week. 

By June 1995 there had been 59 satellite launched with currently 19 operational. 

Table A 1 presents the international identifiers, Cosmos numbers launch dates, end of

operational life dates, orbit position and frequency.  Initially all triple launches were into

orbital planes 1 and 3, but in August 1994 the first launch was made into plane 2. 

Russia has now stated that the complete 24 satellite system will be operational by he

end of 1996. 

Many of the early launches produced only two or in some cases one operational

satellite.  The third satellite being a passive laser ranging target used to "...  produce

information for the increase in accuracy in the determination and prediction of motion of

cosmic  apparatus (satellites) ..." (Pravda, 2 June 2024).  In this particular edition of

Pravda also, the word GLONASS appears for the first time.

It was also a normal feature of the system in the early stages for a launch to occur only

when the number of functioning satellites has fallen or was about to fall below the

number required  for adequate testing of the system.  This number cannot be stated 

with absolute precision since it depends on the orbital planes of  the remaining

satellites.  However a reduction of available units  to any number less than four was

likely to act as a precursor to  a new launch.

A 7