To answer your question you have to go the Code of Federal Rules (CFRs) Title 49 Part 65 for the requirement. I have included them for you bottom line is you need 30-months of hands on training to meet the minimum requirements or attend a Part 147 aviation school and complete the entire course.
I have all of the information about how to obtain an A&P on my personal web site click on mechanic tool box the site is: http://www.stacheair.com
If you need addition information there is a hyper link to my e-mail and I can assist you directly and answer any question regarding the process.
Some people cannot work under the CFRs and complain a lot, but I can tell you being a A&P mechanic has be a great career for me and I must admit I have done very well. I would highly recommend the career field as it is challenging and is in demand.
§ 65.71 Eligibility requirements: General.
(a)To be eligible for a mechanic certificate and associated ratings, a person must— (
1.Be at least 18 years of age;
2.Be able to read, write, speak, and understand the English language, or in the case of an applicant who does not meet this requirement and who is employed outside of the United States by a U.S. air carrier, have his certificate endorsed "Valid only outside the United States";
3.Have passed all of the prescribed tests within a period of 24 months; and
4.Comply with the sections of this subpart that apply to the rating he seeks.
(b)A certificated mechanic who applies for an additional rating must meet the requirements of §65.77 and, within a period of 24 months, pass the tests prescribed by §§65.75 and 65.79 for the additional rating sought.
(a)The following ratings are issued under this subpart:
65.75 Knowledge requirements.
(a)Each applicant for a mechanic certificate or rating must, after meeting the applicable experience requirements of §65.77, pass a written test covering the construction and maintenance of aircraft appropriate to the rating he seeks, the regulations in this subpart, and the applicable provisions of parts 43 and 91 of this chapter. The basic principles covering the installation and maintenance of propellers are included in the powerplant test.
(b)The applicant must pass each section of the test before applying for the oral and practical tests prescribed by §65.79. A report of the written test is sent to the applicant.
§ 65.77 Experience requirements.
Each applicant for a mechanic certificate or rating must present either an appropriate graduation certificate or certificate of completion from a certificated cated aviation maintenance technician school or documentary evidence, satisfactory to the Administrator, of—
(a)At least 18 months of practical experience with the procedures, practices, materials, tools, machine tools, and equipment generally used in constructing, maintaining, or altering airframes, or powerplants appropriate to the rating sought; or
At least 30 months of practical experience concurrently performing the duties appropriate to both the airframe and powerplant ratings.
§ 65.79 Skill requirements.
Each applicant for a mechanic certificate or rating must pass an oral and a practical test on the rating he seeks. The tests cover the applicant's basic skill in performing practical projects on the subjects covered by the written test for that rating. An applicant for a powerplant rating must show his ability to make satisfactory minor repairs to, and minor alterations of, propellers.
§ 65.80 Certificated aviation maintenance technician school students.
Whenever an aviation maintenance technician school certificated under part 147 of this chapter shows to an FAA inspector that any of its students has made satisfactory progress at the school and is prepared to take the oral and practical tests prescribed by §65.79, that student may take those tests during the final subjects of his training in the approved curriculum, before he meets the applicable experience requirements of §65.77 and before he passes each section of the written test prescribed by §65.75.