Not sure if this has been linked yet, just in case it hasn't, here is the program solicitation from DARPA for Project Blackswift.
From the System Requirements Document (an appendix to the above linked doc):

Hypersonic Flight
1.1. The Blackswift testbed shall use a hydrocarbon-fueled turbine-based combined cycle (TBCC) propulsion system reaching and maintaining maximum
sustained Mach number of 6+ for a duration sufficient to attain propulsion system thermal equilibrium or for at least sixty seconds (whichever is
greater). The flight test program shall demonstrate testbed maneuverability at Mach 6+ including execution of an aileron roll and a lateral
maneuver.
1.1.1. Definitions:
1.1.1.1. “Maximum Sustained Mach number” is the maximum Mach number at
which propulsion system thermal equilibrium can be attained at level
cruising flight.
1.1.1.2. “Propulsion System Thermal Equilibrium” is achieved when the
propulsion system reaches a steady state temperature.
1.1.1.3. “Aileron Roll” is a 360 degree coordinated rotation around the
longitudinal axis while maintaining the original heading direction.
1.1.1.4. “Lateral Maneuver” is a turn of at least 1.5 g’s load factor for five (5)
seconds, followed by reversal and return to original heading, at the
maximum sustained Mach number and nominal level flight.
2.0 Thermal Balance
2.1. The Blackswift testbed shall achieve propulsion system thermal equilibrium at the
testbed’s maximum Mach capability without the use of excess fuel for cooling of the
propulsion system (i.e. no overboard fuel dumping).
3.0 Powered Take-Off, Ascent, Acceleration, Cruise, and Landing
3.1. The Blackswift testbed shall take off and land on a runway and shall accelerate,
cruise, and decelerate, using conventional, powered aircraft operating procedures
(e.g., air drop or rocket augmentation shall not be used to meet the requirements)
within a usable flight test range that are consistent within range requirements.
4.0 Flight Test Operational Life
4.1. The Blackswift testbed shall have an operational life of at least two hypersonic flights
at the maximum sustained Mach number on the same testbed following a flight
envelope expansion buildup program with, if necessary, only minor airframe
refurbishment.
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4.2. The Blackswift testbed turn around time between flights shall be consistent with the
proposed flight test schedule, but in any case the time to refurbish and service the
testbed shall not exceed ten (10) days.
5.0 Propulsion System
5.1. The Blackswift testbed shall achieve the hypersonic flight requirements using a
(TBCC) propulsion system consisting of integrated turbojet and ramjet/scramjet
engines combined into a single propulsion flowpath.
5.2. The Blackswift testbed propulsion system design and configuration shall be
representative of propulsion components and propulsion integration schemes used by
a future, reusable, air-breathing hypersonic cruise vehicle.
6.0 Flight Test and Envelope Expansion
6.1. The Blackswift flight test program shall demonstrate flight operability and
performance, including multiple flights to incrementally expand the flight envelope.
7.0 Aircraft Design Capability
7.1. The testbed shall be designed to ensure robust operation with necessary performance
margin including the capability for demonstrating:
7.1.1. Propulsion system operability and thermal balance
7.1.2. Inlet start/un-start/re-start limits
7.1.3. Rejected take-off prior to lift-off
7.1.4. Robust TBCC mode transition flight conditions (accel and decel)
7.1.5. Operation through a range of dynamic pressures consistent with testbed design
limits
7.1.6. Power-off landing
7.1.7. Power-off energy management (speed/wheel brakes, parachutes, etc)
8.0 Flight Test Instrumentation, Data, and Acquisition
8.1. The Blackswift flight test program shall include testbed instrumentation, ground
support, air assets, and data monitoring and acquisition systems to measure and
record sufficient flight test data to determine successful completion of flight test
objectives, satisfying system requirements, and validating ground test data and
modeling and simulation predictions.
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9.0 Aircraft Fault Tolerance, Recovery, and Flight Termination
9.1. The Blackswift testbed shall be fail safe to the maximum extent achievable.
9.2. The Blackswift testbed shall have a flight termination system.