The mechanical response of hybrid carbon nanotubes to applied uniaxial compressive forces has been evaluated inside a transmission electron microscope. The initially crooked nanocolumnar materials had an average elastic modulus of 0.53 GPa, measured in situ via a device based on an atomic force microscope cantilever. To extract this property it was necessary to curtail several sources of error (contact sliding, electronic interferences, etc) and develop the methodology herewith outlined. Since the present study was carried out with a commercially available sample holder, these mechanical studies are pertinent to all those working with one-dimensional structures such as nanorods and nanowires.