> ## Documentation Index
> Fetch the complete documentation index at: https://www.narev.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Descent

> Descent: conditions, actions and checks for the Boeing 737-800.

Use this procedure to prepare the aircraft for the selected arrival and approach. Confirm each required aircraft state before acknowledging the corresponding checklist item.

## General

Verify landing pressurization, recall system annunciations, enter VREF, set the applicable minimums, set or verify navigation radios and select autobrake as needed. Obtain all numerical targets from the assigned arrival data and performance calculation.

Selected pressurization landing altitude is distinct from current cabin altitude. Verify the correct selected target. Confirm the chosen approach family and its required configuration before entry.

### 1. Pressurization: Landing altitude — **Verify**

Verify the pressurization landing-altitude setting against the mission’s destination requirement.

> **Checks and evidence**
>
> **Expected response:** Verify
>
> **Verification:** Read the selected pressurization LAND ALT value; compare it with the approved mission target.

### 2. System annunciator — **Recall**

Recall system annunciations and interpret the actual indications before proceeding.

> **Checks and evidence**
>
> **Expected response:** Recall
>
> **Verification:** Observe the recalled panel’s required results; preserve any active faults in the ledger.

### 3. Approach REF page: VREF — **Enter**

Enter or confirm the landing reference speed (VREF) on APPROACH REF for the selected landing configuration and weight. Follow the [FMC entry and verification steps](https://www.narev.ai/docs/irl-gym/aircraft/manual/fmc-operation.md), then read back the accepted selection.

> **Checks and evidence**
>
> **Expected response:** Enter
>
> **Verification:** Verify the accepted VREF/configuration on the expected page, not only scratchpad text.
>
> **Earlier source wording:** Enter/confirm the approved landing reference speed on the actual APPROACH REF page, using the selected landing configuration and weight.
>
> Use the operating instruction above where it corrects or clarifies this earlier wording.

### 4. Radio/baro minimums — **As needed**

Read the applicable minimums from the selected approach chart. Determine whether they use a radio or barometric reference, then set and verify the value and reference mode.

> **Checks and evidence**
>
> **Expected response:** As needed
>
> **Verification:** Read the selected minima value and its reference mode.
>
> **Earlier source wording:** Resolve the published/approved minima value and whether the procedure uses radio or barometric reference; set and verify both.
>
> Use the operating instruction above where it corrects or clarifies this earlier wording.

### 5. Navigation radio — **Set/verify**

Tune and verify the navigation radios for the selected arrival and approach. Use the installed conventional navigation receiver or multi-mode receiver (MMR), with the frequencies and courses from the selected approach chart.

> **Checks and evidence**
>
> **Expected response:** Set/verify
>
> **Verification:** Verify the active receiver frequency and intended identification/course where available.
>
> **Earlier source wording:** Tune and verify the departure navigation radios using the configured conventional NAV or MMR receiver and approved frequencies/courses.
>
> Use the operating instruction above where it corrects or clarifies this earlier wording.

### 6. Autobrake — **As needed**

Select the autobrake setting required by the landing performance and mission instructions. Verify the selector and required indications.

> **Checks and evidence**
>
> **Expected response:** As needed
>
> **Verification:** Confirm the selected mode and required arming/disarm state.

## Continue after this procedure

Continue with [Approach](https://www.narev.ai/docs/irl-gym/aircraft/procedures/approach.md) when its conditions apply. If descent begins from an initialized scenario, verify the current configuration rather than completing earlier flight phases retrospectively. The source checklist does not declare an automatic transition.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.