Ka8 Flyer,
Your circumstances fit into the grey area of the poorly worded US visa rules. The INA defines the B- and M1- class visas as follows:
INA: ACT 101 - DEFINITIONS
Sec. 101. [8 U.S.C. 1101]
(a) As used in this Act-
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(15) The term "immigrant" means every alien except an alien who is within one of the following classes of nonimmigrant aliens:
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(B) an alien (
other than one coming for the purpose of study or of performing skilled or unskilled labor or as a representative of foreign press, radio, film, or other foreign information media coming to engage in such vocation) having a residence in a foreign country which he has no intention of abandoning and who is visiting the United States temporarily for business or temporarily for pleasure;
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(M) (i) an alien having a residence in a foreign country which he has no intention of abandoning who seeks to enter the United States temporarily and solely for the purpose of pursuing
a full course of study at an established vocational or other recognized nonacademic institution (other than in a language training program) in the United States particularly designated by him and approved by the Attorney General, after consultation with the Secretary of Education, which institution shall have agreed to report to the Attorney General the termination of attendance of each nonimmigrant nonacademic student and if any such institution fails to make reports promptly the approval shall be withdrawn,
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8 CFR 214.1 defines "full course of study" for the F- (academic) and M- (vocational/non-academic) visa classes. For the M-class of visa:
§ 214.2 Special requirements for admission, extension, and maintenance of status.
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(m) Students in established vocational or other recognized nonacademic institutions, other than in language training programs —(1) Admission of student —(i) Eligibility for admission. A nonimmigrant student may be admitted into the United States in nonimmigrant status under section 101(a)(15)(M) of the Act, if:
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(9) Full course of study. Successful completion of the course of study must lead to the attainment of a specific educational or vocational objective. A “full course of study” as required by section 101(a)(15)(M)(i) of the Act means—
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(iii) Study in a vocational or other nonacademic curriculum, other than in a language training program except as provided in § 214.3(a)(2)(iv), certified by a designated school official to consist of at least eighteen clock hours of attendance a week if the dominant part of the course of study consists of classroom instruction, or at least twenty-two clock hours a week if the dominant part of the course of study consists of shop or laboratory work; or
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(v) On-line courses/distance education programs. No on-line or distance education classes may be considered to count toward an M-1 student's full course of study requirement if such classes do not require the student's physical attendance for classes, examination or other purposes integral to completion of the class. An on-line or distance education course is a course that is offered principally through the use of television, audio, or computer transmission including open broadcast, closed circuit, cable, microwave, or satellite, audio conferencing, or computer conferencing.
(vi) Reduced course load. The designated school official may authorize an M-1 student to engage in less than a full course of study only where the student has been compelled by illness or a medical condition that has been documented by a licensed medical doctor, doctor of osteopathy, or licensed clinical psychologist, to interrupt or reduce his or her course of study. A DSO may not authorize a reduced course load for more than an aggregate of 5 months per course of study. An M-1 student previously authorized to drop below a full course of study due to illness or medical condition for an aggregate of 5 months, may not be authorized by the DSO to reduce his or her course load on subsequent occasions during his or her particular course of study.
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There is some additional guidance in the Foreign Affairs Manual (9 FAM 41.61 notes):
http://www.state.gov/documents/organization/87373.pdf
Page 16 of 37 -
9 FAM 41.61 N9.2-1 B-2 Visa for Visitor Who Will Engage in a Short Course of Study
a. Aliens whose principal purpose of travel (see 9 FAM 41.31 N6.1) is tourism, but
who plan to engage also in a short course of study (less than 18 hours per
week) are properly classified for B-2 visas. You must determine whether the
content of the course qualifies as a short course of study. If the student plans
to spend a week or more of full-time study (more than 18 hours per week),
and/or earns academic credit or completion of an academic program of study in
the United States, then an F-1 or M-1 visa is required. You should annotate the
visa as follows: "STUDY INCIDENTAL TO VISIT; Form I-20, Certificate of
Eligibility for Nonimmigrant (F-1) Student Status-for Academic and Language
Students NOT REQUIRED." (See 9 FAM 41.31 N13.6.)
b. An alien enrolling in such a school may be classified B-2 if the purpose of
attendance is recreational or avocational. When the nature of a school's
program is difficult to determine, you should request from DHS
([email address in original PDF]) the proper classification of the program and whether
approval of Form I-20, Certificate of Eligibility for Nonimmigrant (F-1) Student
Status - for Academic and Language Students, will be more appropriate. (See
9 FAM 41.31 N14.8.)
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9 FAM 41.61 N9.2-2 F-1 or M-1 Visa for Visitor Who Will Engage in a Short Term Program
a. An alien may only qualify for an F-1 or M-1 if he or she is or will be engaging in
a full course of study. If a student plans to spend a week or more of full-time
study (more than 18 hours per week) in the United States, an F-1 or M-1 visa is
appropriate. Currently these students would need a new SEVIS ID and new
Form I-20 for each visit.
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In summary a person admitted under a B-class of visa is not permitted to pursue a
course of study (except trivial courses) and a person admitted under an M1-class of visa is required to pursue only a
full course of study.
8 CFR 214.2(b)(7) requires persons pursuing a
course of study to use an M- or F-class of visa, as appropriate, but does not attempt to define "course of study." The abovementioned DOJ memorandum simply states: "
Courses with more substance or that teach a potential vocation, such as flight training, would be considered part of a "course of study" and thus would require approval of a student status."
There is an inconsistency in the visa regulations in as much as persons wishing to pursue short vocational courses which do not satisfy the "full course of study" requirement made in 8 CFR 214.2(m)(9) are offered no legitimate basis on which to be admitted.
The training you intend to pursue - 20 to 25 hours of flying for a US private pilot certificate - should really be done under an M1 visa. Given the choice it is better to fall foul of 8 CFR 214.2(m)(9) than 8 CFR 214.2(b)(7).