UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C.  20549

SCHEDULE 13G

(Amendment No. Five )*


Aerojet Rocketdyne Holdings, Inc.
(Name of Issuer)


Common Stock
(Title of Class of Securities)


007800105
(Cusip Number)


December 31, 2018
(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to
which this Schedule is filed:

[x] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect
to the subject class of securities, and for any subsequent
amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover
page shall not be deemed to be "filed" for the purpose of
Section 18 of the Securities Exchange Act of 1934 ("Act")
or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the
Act (however, see the Notes).














1.  NAME OF REPORTING PERSON
S.S. OR I.R.S. INDENTIFICATION NO. OF ABOVE PERSON:

NewSouth Capital Management, Inc.
Tax ID #: 62-1237220

2.	 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*(a)[ ]
                                                        (b)[ ]

3.	 SEC USE ONLY

4.	 CITIZENSHIP OR PLACE OF ORGANIZATION
    	 Tennessee


NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING
PERSON WITH:

5.	SOLE VOTING POWER
	1,990,854


6.	SHARED VOTING POWER
	None


7.	SOLE DISPOSITIVE POWER
	2,624,207

8.	SHARED DISPOSITIVE POWER
        None


9.	AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING
        PERSON
      2,624,207


10.	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
        CERTAIN SHARES
        N/A


11.	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
        3.4%

12.	TYPE OF REPORTING PERSON*
        I/A








Item 1. (a)  Name of Issuer:

         	 Aerojet Rocketdyne Holdings, Inc. (f/k/a GenCorp Inc.)

Item 1. (b)  Address of Issuer's Principal Executive
             Offices:

		 2001 Aerojet Road
		 Rancho Cordova, CA 95742


Item 2. (a)  Name of Person Filing:

             NewSouth Capital Management, Inc.


Item 2. (b)  Address of Principal Business Office:

             999 S. Shady Grove Rd. Suite 501
             Memphis, TN  38120


Item 2. (c) Citizenship:

            USA


Item 2. (d) Title of Class of Securities:

		Common Stock


Item 2. (e) CUSIP Number:

		007800105


Item 3. (e) /x/ Investment Adviser registered under Section
		203 of the Investment Advisers Act of 1940

Item 4.  Ownership:

(a)	Amount Beneficially Owned:
        2,624,207
(b)	Percent of Class:
        3.4%



(c)	Number of Shares as to which such person has:
(i)	Sole Power to vote or to direct the
        vote:	1,990,854
(ii)	Shared Power to vote or to direct the
        vote:	None
(iii)	Sole Power to dispose or to direct the
        disposition of:	2,624,207
(iv)	Shared Power to dispose or to direct
        the disposition of:	None

Of the 2,624,207 shares being reported, 76,701 or .10% of
the outstanding shares of Common Stock of Aerojet Rocketdyne
Holdings, Inc. are managed by NewSouth Capital Management,Inc.
Through a Thomas Weisel Partners Investment Management
Consulting Program whereby accounts are placed with NewSouth
For management.  Although discretionary responsibility for
the accounts is with NewSouth, Thomas Weisel Partners
retains responsibility for SEC filings should their
cumulative holdings trigger the need for 13G reporting.

Item 5. Ownership of Five Percent or Less of a Class:

If this statement is being filed to report the fact that
as of the date hereof the reporting person has ceased to be
the beneficial owner of more than five percent of the class
of securities, check the following [X].

Item 6.  Ownership of More than Five Percent on Behalf of
         Another Person: N/A

Item 7.  Identification and Classification of the
Subsidiary Which Acquired the Security Being Reported on By
the Parent Holding Company:  N/A

Item 8.  Identification and Classification of Members of
the Group:  N/A

Item 9.  Notice of Dissolution of Group:  N/A
















Item 10.  Certification:

By signing below I certify that, to the best of my
knowledge and belief, the securities referred to above were
acquired in the ordinary course of business and were not
acquired for the purpose of and do not have the effect of
changing or influencing the control of the issuer of such
securities and were not acquired in connection with or as a
participant in any transaction having such purposes or
effect.

After reasonable inquiry and to the best of my knowledge
and belief, I certify that the information set forth in
this statement is true, complete and correct.

Date:	02/12/2019 as of 12/31/2018


Signature:__________________________

Name: 	David M. Newman
Title:	Vice President