> ## 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.

# Securing the aircraft

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

Use this procedure when its prerequisites apply. Confirm each required aircraft state before acknowledging the corresponding checklist item.

## General

Begin shutdown in the assigned parked condition. Set the parking brake and establish the required electrical supply before moving engine start levers to CUTOFF.

The checklist requires fuel pump switches OFF without a listed APU exception. Engine bleed ON is a switch-selection requirement, not an indication that a stopped engine supplies air. Account for the assigned APU and electrical/air configuration.

With Airside Services active, anti-collision OFF can initiate deboarding and cargo unloading.

## Secure

Select the secure procedure when required after shutdown. Its four checks are IRS OFF, emergency-exit lights OFF, window heat OFF and packs OFF. A battery-OFF or mandatory APU-OFF step is not included. Record the actual end condition; secure-checklist completion alone does not establish cold-and-dark.

### 1. IRS mode selector — **Off**

Select the applicable IRS mode selectors OFF. Verify OFF; do not initiate alignment.

> **Checks and evidence**
>
> **Expected response:** OFF
>
> **Verification:** Require both applicable selector positions and, when NAV is required, the approved alignment/position-initialization checks.

### 2. Emergency exit lights — **Off**

Bring the emergency-exit-light switch to OFF for secure and verify it.

> **Checks and evidence**
>
> **Expected response:** OFF
>
> **Verification:** Require a confirmed OFF switch state.

### 3. Window heat — **Off**

Establish the required ON/OFF condition for the applicable window-heat switches using observed current state.

> **Checks and evidence**
>
> **Expected response:** OFF
>
> **Verification:** Use actual switch state and the meaning of each window-heat annunciator.

### 4. Pack switches — **Off**

Set both pack switches OFF. Verify both selector positions using the applicable detent decoding.

> **Checks and evidence**
>
> **Expected response:** OFF
>
> **Verification:** Read both selector states and confirm the requested detent.

## Continue after this procedure

No explicit source transition is declared. Select the next applicable procedure after the required completion and entry conditions are established.


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