Gravitsapa or Gravizapa, transliteration from the Russian
Гравицапа, is the engine based on the principle of the Reactionless propulsion , contradicting the First law of Newton. This engine gets the huge governmental foundation in Russia in the beginning of century XXI. Gravitsapa by Valery Menshikov had been installed at the Russian satellite "Yubileiny", launched in 2008 and reported to affect the trajectory of the satellite.
The need to push anything in order to cause any movement was recognized well before Christ. The sentence GIVE ME A PLACE TO STAND AND I WILL MOVE THE EARTH is attributed to Archimedes . Since that time, there was not so many documents about the inertial propulsion. The most famous (and, according to the story, successful) intent of the support-less propulsion is attributed to Baron Munchausen . Some projects offer the detailed schemes of the inertial propulsion engines .
Not so many researchers consider the support-less propulsion seriously, if at all. Indeed, such a propulsion contradicts the Frist law of Newton: there exist reference frames (so-called Inertial frame of reference) in which all bodies that are far from other bodies, move straight with constant speed or rest immobile. Traditionally, the Support-less propulsion was considered as a nonsense, as some equivalent of the perpetual motion which contradicts the fundamental concepts of physics. Exploring the principle of equivalence of the gravitation and the inertial force, the support-less propulsion can be called also antigravity; the claims on the realization were area of science-fiction, circus illusionists and subject for jokes .
The interest to the Support-less propulsion was boiled up in the beginning of century XXI in Russia, under condition of so-called "vertikal vlasti" (Transliteration from the Russian вертикаль власти) . The superior political power and the ability to eliminate the critical authors  makes an impression of power not only over the Laws of the society, but also over the laws of physics. Within first years of the century XXI, several resalizations of the support-less propulsion were reported. The descriptions reads:
Our institute's staffers have been developing a non-jet propulsion unit for several years in a row, Valery Menshikov, who heads this institute, said in mid-March. A liquid or solid-state propulsive mass moves along a preset tornado-shaped trajectory inside this engine, thereby ensuring sustainable propulsion. Quite possibly, we are witnessing a hitherto unknown interaction between the propulsive mass and little-studied fields, including the gravitation field, Menshikov explained.//
This unique solar-powered engine will have a service life of at least 15 years, developers claim. And it can be switched on 300,000 times, or so.//
The institute's scientists believe their invention can play the part of an attitude-control engine or thruster. It can also be installed on aircraft and ground vehicles.[7,8]. The director of the Scientific Research Institute of Space Research and Production, Valery Menshikov was the most successful in getting funds for the inertial propulsion machine. His apparatus called Gravitsapa is installed at the satellite "Yubileiny" (transliteration from Russian Юбилейный) and launched 24 May 2008 [9,10]. First, the claim was to realize the perpetual motion machine, then the claim was reduced to the inertial propulsion . Of order of milliard dollars are estimated to be necessary for such projects .
The inertial propulsion is developed mainly in Russia for the government's budget. The most of criticism is in Russian
; many Russian references are suggested in the
Russian version of this article.
Mainly, the critics is based on the violation of conservation of the momentum and indicates that the distributors of the budget not know even the First law of Newton. The violation, at the conservation of energy, would break the principle of relativity of the movement . Up to year 2010, no official denouncement of the projects of the inertial propulsion has been issued by the Russian government. The governmental support of the gravitsapa-like progects ruins the public image of the "Russian science", and brings the heavy moral harm to all Russian researchers; especially to those who work in foreign countries.
The activity by Valery Menshikov with gravitsapa-like projects makes an impression of extremely extensive fraud.