Still Cannot Make Planes

Earlier this month, I noted that Boeing asked for an exemption for the engine deicing system on its 737 MAX aircraft, which could blow up an engine if operated in non-icing conditions for more than 5 minutes.

As a result of the cluster fuck with the fuselage plug blowing out, Boeing has has withdrawn the request.

My guess is that this was done grudgingly, and only after the FAA made it clear that they would not get their waiver as things currently stand.

I do not think that Boeing management had an attack of conscience.

I do not thing that they have a conscience:

Under intense political pressure, Boeing on Monday withdrew its request for an exemption from key safety regulations to allow the 737 MAX 7 to be certified to carry passengers.

“We have informed the FAA that we are withdrawing our request for a time-limited exemption relating to the engine inlet de-icing system on the 737-7,” Boeing said in a statement. “We will instead incorporate an engineering solution that will be completed during the certification process.”

This means entry into passenger service of the MAX 7, the smallest model of the MAX family, will be significantly delayed until Boeing can design a fix for the flawed design and get it approved by the Federal Aviation Administration.

………

The FAA had determined last summer that a design flaw uncovered in the MAX’s engine inlet de-icing system could be potentially catastrophic.

The MAX’s engine inlet, the circular part at the front end of the pod surrounding the engine — known as a nacelle — is made from carbon composite, unlike earlier model 737s, which have a metal inlet.

Flying through cold, water-saturated air, the de-icing system — similar in purpose to the defroster on a car — blows hot air onto the engine inlet to prevent a buildup of ice.

But Boeing discovered after the MAX entered service that if the system remained switched on after leaving the icy air, it could overheat and damage the composite structure, possibly leading it to break off the nacelle.


In an August Airworthiness Directive, the FAA stated that debris from such a breakup could penetrate the fuselage, putting passengers seated at windows behind the wings in danger, and could damage the wing or tail of the plane, “which could result in loss of control of the airplane.”

Gee, that sounds bad.

………

However, that compromise solution couldn’t work for a jet like the MAX 7 that is not yet certified. To get that approval to carry passengers, it must meet all safety regulations.

Hence Boeing’s petition for a formal exemption for the MAX 7 from the safety standards until it designed a solution.

Yeah, their solution is to add a page to the flight manual.  This is not adequate.

If an aircraft if flying in icing conditions, even if it is certified for those conditions, pilots will have their hands full, and turning off bleed air as soon as they are out of icing conditions can be something that gets missed.

The fact that there are thousands of aircraft currently flying with a deicing system that can cause a catastrophic failure today does not reassure.