Back to home pageProposed MAX Design Enhancements

Home > History and Variants > 737 Max > MAX Differences > Design Enhancements


Illustrated technical information covering Vol 2 Over 800 multi-choice systems questions Study notes and technical information Close up photos of internal and external components A compilation of links to major 737 news stories with a downloadable archive Illustrated history and description of all variants of 737 Detailed tech specs of every series of 737 Databases and reports of all the major 737 accidents & incidents General flightdeck views of each generation of 737's Description & news reports of Advanced Blended Winglets Press reports of orders and deliveries A collection of my favourite photographs that I have taken of or from the 737 Details about 737 production methods A compilation of links to other sites with useful 737 content History and Development of the Boeing 737 - MAX A quick concise overview of the pages on this site


25 Jun 2020 - Boeing asked by regulators to consider further design enhancements to the MAX

EASA and Transport Canada are requesting “design enhancements” to the MAX beyond the fixing of MCAS. These will not require action before it is reintroduced into service, but probably within a couple of years. The requested changes are:

The MAXs two AoA probes

Since the MAX has only two AoA probes, the FCCs do not know which one to trust in the event that one misbehaves. It is probably significant that this concern is raised by EASA and the Airbus has three AoA probes (because the A320 is more FBW than a 737). EASA is not necessarily insisting upon a third probe but a suggestion would be creating a synthetic sensor which computes AoA data from a variety of other existing sources on the aircraft. Boeing already uses synthetic airspeed on the 787 so this is achievable, albeit expensive and time-consuming.

Confusing Multiple Warnings

In both MAX accidents multiple warnings were generated as a result of a single AoA fault. EASA believe that this is unsatisfactory. It is possible that EASA are again comparing the 737 with the A320 and its ECAM system which tries to prioritise multiple failures to assist the crew but how this can be achieved with a master caution system is hard to know.

The Stick Shaker

In both MAX accidents the stick shaker and clacker were vibrating and sounding throughout the entire flight from unstick to impact. Transport Canada are requesting a way to silence these warnings, either by pulling circuit breakers or an inhibitor, if the crew consider them to be erroneous. This would reduce noise and stress levels in the flightdeck thereby making the situation easier to handle.

The FAAs view is that Boeing must address these concerns.
See more details about the book

All of the information, photographs & schematics from this website and much more is now available in a 374 page printed book or in electronic format.

*** Updated 18 Apr 2020 ***

The 737 Tech Site on Facebook The 737 Tech Site on Twitter The 737 Tech Site on Instagram


Footer block

This site has had visitors to date.