Orbital Minotaur I - Manual (Page 47)

Minotaur I User’s Guide Section 5.0 – Payload Interfaces
5.2.2. Orbital Supplied Mechanical Interface
Control Drawing
Orbital will provide a toleranced Mechanical
Interface Control Drawing (MICD) to the payload
contractor to allow accurate machining of the
fastener holes. The Orbital provided MICD is the
only approved documentation for drilling the
payload interface.
5.2.3. Standard Non-Separating Mechanical
Interface
Orbital’s payload interface design provides a
standard interface that will accommodate multiple
payload configurations. The Minotaur I baseline is
for payloads that provide their own separation
system and payloads that will not separate. The
standard interface is a 986 mm (38.81 in.) diameter
bolted interface. A butt joint with 60 holes (0.281 in. diameter) designed for ¼” fasteners is the payload
mounting surface as shown in Figure 5.2.3-1.
The Minotaur I avionics section is designed to accommodate a 680 kg (1500 lbm) payload with a CG 762
mm (30 in.) above the fixed interface flange. Therefore, as an initial guideline, payload mass times its CG
location above this fixed interface needs to be less than or equal to a mass moment of 51,820 kg-cm
(45,000 lbm-in.). The payload mass and CG location must include the Payload Attach Fitting (PAF)
hardware (adapter cone, separation system, isolation system, etc.), in addition to the actual spacecraft
mass properties.
5.2.4. Optional Mechanical Interface
Alternate or multiple payload configurations can be accommodated with the use of a variety of payload
adapter fittings. Minotaur I launch vehicles allow flexibility in mounting patterns and configurations.
5.2.4.1. Dual and Multi Payload Adapter Fittings
The Minotaur launch vehicle design flexibility and performance readily accommodates multiple spacecraft
that are independently deployed when required as a non-standard service. Minotaur I has demonstrated
multiple payload adapter systems, such as the JAWSAT mission, which successfully deployed five
satellites and six picosats, as well as load bearing satellites such as the COSMIC mission, which
successfully deployed six independent spacecraft.
5.2.4.1.1. Load-Bearing Spacecraft
Use of load-bearing spacecraft maximizes use of available volume and mass. In this case, the aft load-
bearing spacecraft interfaces directly to the avionics assembly interface and to the forward spacecraft via
pre-determined spacecraft to spacecraft interfaces.
The requirements levied upon spacecraft in this scenario are those involving mechanical and electrical
compatibility with the interfacing spacecraft as well as the launch vehicle. Structural loads from forward
satellites during all flight events must be transmitted through the aft satellites to the Minotaur I. Orbital will
Figure 5.2.3-1. Standard, Non-separating 38.81”
Diameter Payload Mechanical Interface
Release 3.0 March 2014 34