14 CFR §382.13

1. (a)As a carrier, you must modify your policies, practices, and facilities when needed to provide nondiscriminatory service to a particular individual with a disability, consistent with the standards of section 504 of the Rehabilitation Act, as amended.
2. (b)This requirement is part of your general nondiscrimination obligation, and is in addition to your duty to make the specific accommodations required by this part.
3. (c)However, you are not required to make modifications that would constitute an undue burden or would fundamentally alter your program.