Boeing 737 CDU Practice Scenarios

Learn the RTE and PERF INIT pages — the backbone of every Boeing 737 flight setup.

Program a short-haul Boeing 737 flight from EGLL to LFPG. Covers RTE, PERF INIT, and TAKEOFF REF.

You typed the wrong destination. Learn how to overwrite an existing field on the RTE page — the same workflow ATC reroutes use.

Halfway to Paris, ATC says LFPG is closed for weather. Update the FMC to divert to Brussels (EBBR) — the same workflow real pilots use under ATC pressure.

Before you program a flight you need to know where everything lives. Visit each major CDU page in sequence so the layout is no longer a maze. No data entry — just navigation.

Your first procedure scenario on the CDU. Phoenix → Las Vegas is a short desert hop (~220 nm) flown constantly by Southwest, American and Spirit. The drill: enter the route, then program a departure (SID) out of KPHX and an arrival (STAR) into KLAS from the DEP/ARR page.

Most pilots type a cost index from their OFP and never think about it again. In this scenario you try three values — 0, 30, and 80 — on the PERF INIT page to feel what the number actually controls: the trade-off between speed and fuel burn.

Enter takeoff flaps and V-speeds (V1, Vr, V2) on the TAKEOFF REF page for a Madrid → London 737-800 departure. These numbers come from the OFP, calculated by the airline's performance software for today's weight, runway, wind and temperature.

Reduced-thrust takeoff (Boeing calls it ATM — Assumed Temperature Method) tells the engines it is hotter outside than it really is, so they produce less thrust. Try three values to feel the trade-off between engine wear and performance margin.

You're cruising at FL340 westbound over the Atlantic on a 737-800. As fuel burns off the aircraft can fly higher and more efficiently. Check OPT and MAX altitudes on the CRZ page, then step up to FL360.

Before flying any approach, real Boeing 737 pilots verify the inbound navaid frequencies on REF NAV DATA. Look up two VORs you would expect to use on the EGLL ILS 09L approach: DVR (Dover) for the initial fix and BIG (Biggin) for the final intermediate fix.

Fix the two errors every 737 pilot hits when entering an airway on the CDU RTE page — "NOT IN DATABASE" (unknown airway) and "INVALID ENTRY" (a waypoint that isn't on the airway). Learn to read each message and insert J146 correctly on a Los Angeles to New York route.

The single biggest difference between the Boeing CDU and the Airbus MCDU: on the 737, nothing you change takes effect until you press EXEC. Learn the MOD-vs-ACT route and the white EXEC light by staging a direct-to and committing it.

Decode the box-prompt route discontinuity on the 737 LEGS page — what it is, why the FMC inserts it, and how to close the gap and EXEC it active. The Boeing way differs from the Airbus: closing the gap is staged until you press EXEC.

Before the FMC will work, the inertial reference system (IRS) must be aligned with a known position. Learn where POS INIT lives, how to enter the reference airport, and how to set the IRS position to start alignment.