UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported): February 4, 2015

HENNESSY CAPITAL ACQUISITION CORP.

(Exact name of registrant as specified in its charter)

Registrant’s Telephone Number, Including Area Code: (713) 300-8242

Not Applicable

(Former Name or Former Address, If Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Item 3.01 Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

As previously reported in a Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission (“SEC”) on August 13, 2014, Hennessy Capital Acquisition Corp. (the “Company”) received a written notice on August 7, 2014, from the staff of the Listing Qualifications Department of the NASDAQ Stock Market (the “Staff”) indicating that the Company was not in compliance with Listing Rule 5550(a)(3) (the “Minimum Public Holders Rule”), which requires the Company to maintain a minimum of 300 public holders for continued listing on the NASDAQ Capital Market (“Nasdaq”). On September 22, 2014, the Company submitted a plan to Nasdaq to regain compliance with the Minimum Holders Rule and ensure compliance with Nasdaq’s initial listing requirements at closing. On September 30, 2014, the Staff granted the Company an extension until February 3, 2015 to obtain stockholder approval of its initial business combination with School Bus Holdings Inc. (“SBH”) which, through its subsidiaries, conducts its business under the “Blue Bird” name (the “Business Combination”), consummate the Business Combination and demonstrate compliance with Nasdaq’s initial listing requirements.

On February 4, 2015, the Company received a letter from the Staff stating that the Company had failed to consummate the Business Combination by February 3, 2015, and that, accordingly, the Staff has determined to initiate procedures to delist the Company’s securities from Nasdaq, unless the Company appeals such determination on or before February 11, 2015. The Company intends to appeal the Staff’s delisting determination in front of a hearings panel and the Company’s securities will continue to trade on Nasdaq while such appeal is pending. There is no assurance that the Company will be successful in its appeal of the delisting determination.

Additional Information about the Business Combination

The Company has filed with the SEC a definitive proxy statement in connection with the Business Combination and other matters and, beginning on January 21, 2015, mailed the definitive proxy statement and other relevant documents to stockholders of the Company as of the January 2, 2015 record date for the special meeting of Company stockholders. Stockholders of the Company and other interested persons are advised to read the definitive proxy statement and any other relevant documents (including the supplement to the definitive proxy statement, when available) that have been or will be filed with the SEC in connection with the Company’s solicitation of proxies for the special meeting of Company stockholders because these documents will contain important information about the Company, SBH and the Business Combination. Stockholders may also obtain a free copy of the definitive proxy statement, as well as other relevant documents that have been or will be filed with the SEC (including the supplement to the definitive proxy statement, when available), without charge, at the SEC’s website located at www.sec.gov or by directing a request to Daniel J. Hennessy, Chairman and Chief Executive Officer, 700 Louisiana Street, Suite 900, Houston, Texas, 77002, (312) 876-1956.

Participants in the Solicitation

The Company and its directors and executive officers and other persons may be deemed to be participants in the solicitations of proxies from the Company’s stockholders in respect of the Business Combination and the other matters set forth in the definitive proxy statement. Information regarding the Company’s directors and executive officers and a description of their direct and indirect interests, by security holdings or otherwise, is contained in the Company’s definitive proxy statement for the Business Combination, which has been filed with the SEC.

Forward-Looking Statements

This Current Report on Form 8-K may include forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this Current Report on Form 8-K that address activities, events or developments that the Company expects or anticipates will or may occur in the future are forward-looking statements and are identified with, but not limited to, words such as “believe” and “expect”. These statements are based on certain assumptions and analyses made by the Company in light of its experience and its perception of historical trends, current conditions and expected future developments as well as other factors it believes are appropriate in the circumstances. Actual results may differ materially from those expressed herein due to many factors such as, but not limited to, the ability to satisfy closing conditions for the Business Combination, including stockholder and other approvals, the performances of the Company and Blue Bird, the ability of the combined company to be successful in its appeal of the delisting determination by the Staff and to meet the Nasdaq Capital Market’s listing standards, including having the requisite number of stockholders, and the risks identified in the Company’s prior and future filings with the SEC (available at www.sec.gov), including the Company’s definitive proxy statement filed in connection with the Business Combination (and the supplement to the definitive proxy statement, when available) and the Company’s final prospectus dated January 16, 2014. These statements speak only as of the date they are made and the Company undertakes no obligation to update any forward-looking statements contained herein to reflect events or circumstances which arise after the date of this Current Report on Form 8-K.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.