How do I get the MSFS F/A-18 Hornet to fly supersonic (above 680 kts)?

Getting the default MSFS F/A-18 past ~680 knots (and into supersonic)

What you’re seeing is usually normal.
Most folks are watching IAS and expecting it to climb forever.
Supersonic is about Mach, and that comes much easier at altitude.

1) Verify what you’re actually reading

• If you’re staring at KIAS, it can “hang” around the 600–700 range.
• Watch Mach (or TAS) once you’re higher up.
• You can be pushing Mach 1+ with an IAS that does not look crazy.

2) Simple repeatable test profile
Do this with a clean jet and calm weather.
Keep it boring and straight until you’re fast.

1. Take off and retract everything. Gear up, flaps up, speedbrake in.
2. Climb to roughly 30,000–40,000 ft.
3. Level off and let the speed build in level flight.
4. Set full throttle and light the afterburner.
5. Hold a shallow pitch. Keep AoA low and wings level.
6. Give it time. Don’t yank it into turns while accelerating.

If you try this down low, drag is brutal.
You’ll hit a wall and assume it’s “capped.”

3) Common “mystery drag” checks
These bite people all the time.

• Speedbrake not fully stowed.
• Flaps not fully up.
• Flying nose-high while accelerating.
• Any steady turn or high-G maneuver.
• Autopilot modes holding altitude aggressively, causing high AoA.

4) Don’t climb hard while you’re trying to accelerate
A steep climb trades speed for altitude fast.
Get up there first, then accelerate level.
Or do a very shallow climb while in burner.

5) Sanity check: what “680” usually means
If 680 is KIAS, that’s not a supersonic indicator.
At altitude, watch the Mach readout.
That’s the number that matters for “supersonic.”

A few quick questions so we can pin it down

• PC or Xbox?
• What altitude are you trying to break Mach 1 at?
• Are you reading IAS or Mach when you say “680 kts”?
• Any assistance options, autopilot, or control bindings that might be holding speedbrake or trim?