  The Large Observatory for X-ray Timing (LOFT) is one of the four candidate
ESA M3 missions considered for launch in the 2022 time-frame. It is
specifically designed to perform fast X-ray timing and probe the status of the
matter near black holes and neutron stars. The LOFT scientific payload is
composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD
is a 10 m2-class pointed instrument with 20 times the collecting area of the
best past timing missions (such as RXTE) over the 2-30 keV range, which holds
the capability to revolutionize studies of X-ray variability down to the
millisecond time scales. Its ground-breaking characteristic is a low mass per
unit surface, enabling an effective area of ~10 m^2 (@10 keV) at a reasonable
weight. The development of such large but light experiment, with low mass and
power per unit area, is now made possible by the recent advancements in the
field of large-area silicon detectors - able to time tag an X-ray photon with
an accuracy <10 {\mu}s and an energy resolution of ~260 eV at 6 keV - and
capillary-plate X-ray collimators. In this paper, we will summarize the
characteristics of the LAD instrument and give an overview of its capabilities.

Instrumentation and Methods for Astrophysics