The opinion
PRETTYMAN, Circuit Judge
(concurring).
I concur in the result and in the opinion except that the question seems to me closer than my brother BASTIAN indicates it is to him. If inability to participate in a given carriage because of the time necessarily consumed in a certification proceeding constitutes an unusual circumstance in the operation of the applying carrier, and an undue burden upon it, very little is left of the requirements for certification. The certification section of the Act and the exemption section, under that view, would appear to be merely two alternative methods by which the Board can authorize operation. It seems to me Congress must have meant the exemption provision to be more restricted than that. On the other hand, not to participate in a given carriage, because of lack of a certificate and inability to get one promptly, does seem to be an undue burden, although it is due perhaps to the limited extent of the carrier’s operation rather than to unusual circumstances. And I think, so far as I am able to ascertain, that many exemptions from the certification requirements have been granted upon some such theory. At this point the weight of the administrative construction falls into the scale. And that weight tips the balance, in my view, in favor of affirmance'.I realize too that this case does not necessarily rest upon so broad a concept of the exemption requirements as I have posited, because the experimental carriage of the mail with which this case is concerned may well be completed before certification proceedings can be completed. In such event denial of an exemption would be a total and final deprivation of participation. That is not the case in the usual application for exemption.