# Primary Flight Data (PFD)
This page contains all the basic aircraft instrumentation and information necessary to fly the MV-22B.
Figure: Primary Flight Data
1. **Nacelles Indicator:** Indicates the angle of nacelles in degrees. It also visualizes the “Conversion Corridor” (See Performance for more details). Upper and lower limits based on airspeed are shown as two red indicators, safe area is in green.
2. **Indicated Airspeed** (Knots)
3. **Altitude Indicator** (Feet)
4. **Vertical Speed Indicator** (Feet/min): A warning red line appears below 60 knots IAS.
{% hint style="danger" %}
Vertical speeds inferior to 1500 ft/min that may result in Vortex Ring State (VRS). Avoid the red line when flying at low speeds/high nacelle angles.
{% endhint %}
5. **Radio Altimeter:** Activates at an altitude between 1-5000ft (min altitude can be set in the CDU)
6. **Artificial Horizon**
7. **Interm Power:** Green = normal, Yellow = caution, Red = warning, Red Blinking = engine overstress
{% hint style="danger" %}
Engines cannot sustain full throttle for longer than 60 seconds. If Interm Power is blinking, reduce throttle to at least 98% for a few seconds to reduce stress on the engines.
{% endhint %}
8. **Heading/Compass Indicator**
9. **VOR/Waypoint Information:** Bearing, distance, estimated time arrival.
10. **Autopilot Active Data**: (not visible on screenshot)
