MEL Expiry Calc vs B737 Maintenance Mastermind

Stay fast and organized during line ops. MEL Date Calc helps you calculate MEL expiries in seconds and keeps your daily callouts in one place. Switch between Local and UTC, log defects by tail, attach Tech Log photos, and generate a clean, share-ready PDF for the day. The MEL calculator is free to use. Logging, photos, and PDF reporting are available with Pro. Pro also removes ads. -MEL Dates Calculate common MEL deadlines (B C D) View results in Local or UTC Clear, readable layout designed for quick checks -Deferred Log (Pro) Track daily line maintenance callouts by tail Save key details (defect, WO, TL page) Mark items as done once actioned (handover, coordination, or system entry) Search and filter your entries anytime -Tech Log Photos and PDF Report (Pro) Attach Tech Log photos to each entry Generate a daily PDF report with tail MEL category and defect details Add large full-page photo pages for readability (ideal for Tech Log Book photos) Share the report via WhatsApp email or any supported app -Pro (Lifetime unlock) Removes ads (ad-free experience) Unlock Deferred Log Tech Log photo attachments PDF report generation and sharing Privacy No account required. Photos you attach remain on your device unless you choose to share them.

B737 Maintenance Mastermind is an independent quick-reference and utility app designed to support aircraft technicians, engineers, mechanics, and aviation professionals working with Boeing 737 NG and MAX aircraft. The B737MM app combines fast offline tools with secure premium reference modules, helping users quickly find maintenance-related information, calculations, references, and troubleshooting guidance during study, training, planning, or daily technical routines. FREE TOOLS • MEL Calculator Quick helper for standard dispatch time limit calculations. • Unit Converter Fast conversion of common aviation units, including pressure, temperature, volume, weight, and fuel-related values. • Fuel Calculator Useful fuel uplift and density calculation tool for quick planning and cross-checking. • Abbreviations Dictionary Large searchable glossary of aviation, maintenance, and technical abbreviations. PREMIUM REFERENCE MODULES • Alerts Searchable cockpit alert, status, and message references with related technical context. • Flags Reference guide for PFD, ND, FMC/CDU, and display flags. • BITE Built-In Test Equipment reference module with test access information and related troubleshooting links. • MEL Reference Fast searchable Minimum Equipment List reference support for NG/MAX style workflows. • CDL Reference Configuration Deviation List reference module for missing or deferred aircraft configuration items. • Circuit Breakers / CB ATA-grouped circuit breaker reference with panel-related information. • Lights Cockpit, annunciator, and system light reference module with related system context. • Location Aircraft component, access panel, service panel, antenna, and equipment location references. • STA Map Station, frame, stringer, waterline, and aircraft location reference helper for quick orientation. • Visual Panels Interactive visual reference for cockpit panels and related light/panel locations. • Support & Materials Technical support notes, fastener/material references, practical troubleshooting notes, and maintenance helper information. PREMIUM ACCESS Premium reference modules open with an auto-renewable yearly subscription (with a 3-day free trial for eligible users) or a one-time lifetime purchase, both offered in the app. Payment is charged to your Apple Account at confirmation of purchase. The subscription renews automatically unless it is cancelled at least 24 hours before the end of the current period, and your account is charged for renewal within 24 hours before the end of the current period. You can manage or cancel your subscription in your Apple Account settings at any time after purchase. Use Restore Purchases in the app to restore access on a new device. Some premium content requires internet access for first download, access verification, or content updates. Once downloaded, content is available on the device for fast access. IMPORTANT DISCLAIMER This application is an independent reference and training support tool. It is not official Boeing documentation and is not affiliated with, endorsed by, sponsored by, or associated with The Boeing Company, any airline, aircraft operator, maintenance organization, or aviation authority. The information in this app is provided for educational, training, and general reference purposes only. The official Aircraft Maintenance Manual (AMM), Fault Isolation Manual (FIM), Illustrated Parts Catalog (IPC), Wiring Diagram Manual (WDM), Structural Repair Manual (SRM), and the operator-approved MEL/CDL are the only official sources and must always take precedence. Do not use this application as the sole source for aircraft maintenance actions, dispatch release decisions, operational decisions, or work on an actual aircraft. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://b737mm.com/privacy/