[en] The new type of a gravitational neutron spectrometer for the energy range E=0.001-1 eV is described. The neutron energy determination is performed by means of the time-of-flight method. The spectrometer provides the energy solution of several orders higher as compared with the known gravitational spectrometers. Under the conditions of pulsed fast reactors IBR-2 and IBR-30 operation using the proposed gravitational spectrometer with collimater slits of 0.3 mm height on the 1000 metre flight base the neutrons in the energy range E=0.1-10 eV can be monochromated with energy resolution 0.05 - 50%. The gravitational spectrometer experiment has been conducted at the IBR-30 operation in the reactor regime with average reactor thermal capacity of 15 kW assuring thermal neutron average flux on the moderator surface of approximately 3x10¹⁰ n/cm²xs, neutron pulses frequency being 4Hz, duration - 100 μs. The energy resolution obtained in the experiment is somewhat worse as compared with the calculation, it constitutes approximately 8%. The possibility of experimental neutron charge measurement at the 10^-11-10^-14 level accuracy, 10^-6 level gravity constant, 10^-7 level spin dependence and 10^-7 level neutron mass is substantiated