Since about 2005, a list of the AAR interchange rule dates has been posted in the FILES section of this group 😉 It is even in both WORD and EXCEL formats depending on your preference.
That file, when searched for "geared" or "power" yields the following:
January 1, 1937, "Geared handbrakes required on all newly-built or newly-rebuilt cars."
There is no subsequent ban (AAR interchange) or outlaw (Federal law) date given for geared handbrakes.
As a reminder to some of our list members, geared (or "power") handbrakes does NOT mean exclusively horizontal shaft/vertical wheel handbrakes. Many vertical shaft/horizontal wheel installations had gearing to assist the brakeman in applying the brakes and would therefore have been considered "allowed" under these rules.
From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Bob Chaparro via Groups.Io <chiefbobbb@...>
Sent: Saturday, July 6, 2019 1:48 AM
Subject: [RealSTMFC] Handbrakes
I understand that in 1937 power (geared) handbrakes required on all newly-built or newly-rebuilt cars.
Were non-power handbrakes every specifically outlawed or banned?