Block DM has corrected orbital injection errors of Proton-K LV

On June 10th, 2002 the next launch of Proton-K LV carrying Block DM
11C861-01 (US DM) developed and manufactured by RSC Energia was performed.
Express-A spacecraft ordered by Rosaviakosmos under the Federal Space
Program has been successfully placed into target orbit.
During in-flight LV operation allowable errors in reference orbit
(inclination) injection accuracy were two times exceeded. However, due to
Block DM control system existing capability relative to automatic correction
of setup parameters of US main engine ignitions, as well as the implemented
correction capability via MCC radio channel (with due regard for the
ballistic analysis of transfer orbit) of the mission task setups at the time
of the second ignition of Block DM, the parameters of SC target orbit were
provided with a high accuracy:

Parameter Nominal value Actual value Deviation Tolerance

Period (T), s 24.12.04,0 24.13.18,4 74,4 ±270

Eccentricity (e) 0,0000 0,0007 0,0007 0,0035

Inclination (i),

deg. min. sec. 00.12.00 00.14.23 00.02.23 ±00.06.00

Longitude of ascending node (l),

deg.min.sec 90.13.02 90.09.42 -00.03.20 ±00.60.00