Military Technical Institute Belgrade (Serbian: VTI - Vojnotehnički Institut Beograd (VTI)) is a major Serbian aircraft and weapons designer, headquartered in Belgrade, Serbia and governed by the Serbian Ministry of Defence. VTI is a top-level military scientific research institution in Serbia, dealing with research and development (R&D) of new weaponry and military equipment as well as with upgrade of the inventory for all three services of the Army: Land Forces, Air Force and River flotilla.