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Exhibit 99.5

PRO FORMA COMBINED FINANCIAL INFORMATION

    The following pro forma combined financial information has been prepared to reflect the Thiokol acquisition and the related financing. The pro forma combined income statement has been prepared as if each of these transactions occurred on April 1, 2000, while the pro forma combined balance sheet has been prepared as if each of these transactions occurred on March 31, 2001.

    Our fiscal year ends on March 31 of each year while Thiokol's fiscal year ends on December 31 of each year. Accordingly, as permitted by Regulation S-X under the Securities Act of 1933, as amended, for purposes of the pro forma combined income statement, we have combined our historical results for the year ended March 31, 2001 with Thiokol's historical results for the year ended December 31, 2000. For purposes of the pro forma combined balance sheet, we have combined our historical financial position as of March 31, 2001 with Thiokol's historical financial position as of December 31, 2000.

    The Thiokol acquisition will be accounted for under the purchase method of accounting. Under this method of accounting, the identifiable assets and liabilities of the Thiokol business will be adjusted to their estimated fair values. In connection with the acquisition of Cordant by Alcoa in May 2000, the Thiokol assets were adjusted to their estimated fair values. The historical combined financial information for Thiokol under the caption "Successor" reflects this adjustment and the allocation of the purchase price. We will review these fair values and, as a result, the adjustments made by Alcoa may be further adjusted.

    Prior to the May 25, 2000 acquisition by Alcoa, Thiokol was a division of Cordant. The historical combined income statement for Thiokol for the periods from January 1, 1998 to May 25, 2000 is presented based on Cordant's accounting policies and is included under the caption "Predecessor." The historical combined income statement for Thiokol for the period from May 26, 2000 to December 31, 2000 is presented based on Alcoa's accounting policies and is included under the caption "Successor."

    The pro forma combined financial information has been prepared based on the foregoing and on other assumptions described in the related notes.

    The pro forma combined financial information should be read together with Alliant Techsystem Inc.'s historical consolidated financial statements, which have been previously filed with the Securities and Exchange Commission, and those of Thiokol, including the related notes, which are included in this Current Report on Form 8-K on page F-1. The following pro forma combined financial information does not purport to be indicative of the financial position or results of operations that would have been reported had the transactions been effected on the dates indicated, or which may be reported in the future.

    Thiokol results for the year ended December 31, 2000 include a full allocation of Cordant corporate office expenses for the period from January 1 to May 25, 2000 and an allocation of Alcoa Industrial Components Group expenses for the period from May 26 to December 31, 2000 under Alcoa ownership.

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PRO FORMA COMBINED INCOME STATEMENT
Year Ended March 31, 2001
(dollars in thousands, except per share information)

		Historical
		Alliant			Thiokol
		Year Ended March 31, 2001			Predecessor for the Period from January 1 to May 25, 2000		Successor for the Period from May 26 to December 31, 2000		Pro Forma Adjustments			Pro Forma Combined
Sales		$	1,141,949		$	233,258	$	379,694		—		$	1,754,901
Cost of sales			905,574			189,612		308,911	$	2,236	(a)		1,406,333
Research and development			11,575			3,072		4,561		—			19,208
Selling			24,372			2,224		3,113		—			29,709
General and administrative			64,334			3,392		11,476		—			79,202
Income from operations			136,094			34,958		51,633		(2,236	)		220,449
Interest expense			(33,738	)		—		—		(63,081	)(b)		(96,819	)
Interest income			1,038			—		—		—			1,038
Income from operations before income taxes			103,394			34,958		51,633		(65,317	)		124,668
Income tax provision			35,473			13,626		20,479		(27,711	)(c)		41,867
Income before extraordinary loss			67,921			21,332		31,154		(37,606	)		82,801
Extraordinary loss on early extinguishment of debt, net of income taxes			—			—		—		(9,484	)(d)		(9,484	)
Net income (loss)		$	67,921		$	21,332	$	31,154	$	(47,090	)	$	73,317
Basic earnings per share:
	Continuing operations	$	4.92									$	5.99
	Extraordinary Loss		—										(.69	)
	Net income	$	4.92									$	5.30
Diluted earnings per share:
	Continuing operations	$	4.80									$	5.85
	Extraordinary loss		—										(.67	)
	Net income	$	4.80									$	5.18
Weighted shares outstanding:
	Basic		13,815										13,815
	Diluted		14,155										14,155

See Notes to Pro Forma Combined Financial Statements.

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PRO FORMA COMBINED BALANCE SHEET
As of March 31, 2001
(dollars in thousands)

				Historical
				Alliant as of March 31, 2001			Thiokol as of December 31, 2000		Pro Forma Adjustments			Pro Forma Combined
ASSETS
	Cash and cash equivalents			$	27,163		$	12	$	(3,279	)(e)	$	23,896
	Receivables				214,724			118,666		18,218	(a)		351,608
	Net inventory				54,136			37,931		(25,931	)(a)		66,136
	Deferred income tax asset				16,478			27,776		—			44,254
	Other current assets				20,322			111		—			20,433
			Total current assets		332,823			184,496		(10,992	)		506,327
	Net property, plant and equipment				303,188			314,636		—			617,824
	Goodwill and other intangible assets				117,737			263,254		89,446	(a)		470,437
	Prepaid and intangible pension assets				106,048			163,213					269,261
	Deferred charges and other non-current assets				19,708			29,026		27,656	(f)		76,390
			Total assets	$	879,504		$	954,625	$	106,110		$	1,940,239
LIABILITIES AND STOCKHOLDERS' EQUITY
	Current portion of long-term debt			$	69,200		$	—	$	(52,032	)(g)	$	17,168
	Line of credit borrowings				—			—		3,000	(g)		3,000
	Accounts payable				71,758			27,633		—			99,391
	Contract advances and allowances				34,494			16,095		—			50,589
	Accrued compensation				38,487			23,761		—			62,248
	Accrued income taxes				11,873			—		—			11,873
	Other accrued liabilities				66,151			22,512		677	(a)		89,340
			Total current liabilities		291,963			90,001		(48,355	)		333,609
	Long-term debt				207,909			—		779,216	(g)		987,125
	Deferred income taxes				—			84,615		—			84,615
	Post-retirement and post-employment benefits liability				108,203			113,710		—			221,913
	Other long-term liabilities				73,097			51,032		—			124,129
			Total liabilities		681,172			339,358		730,861			1,751,391
	Contingencies
	Common Stock—$.01 par value
		Authorized—20,000,000 shares
		Issued and outstanding—14,070,569 shares			185			—		—			185
	Additional paid-in-capital				231,598			—		—			231,598
	Retained earnings				265,180			—		(9,484	)(d)		255,696
	Parent company equity				—			615,267		(615,267	)(a)		—
	Unearned compensation				(3,854	)		—		—			(3,854	)
	Other comprehensive income				(6,140	)		—		—			(6,140	)
	Common stock in treasury, at cost—4,426,202 shares				(288,637	)		—		—			(288,637	)
			Total stockholders' equity		198,332			615,267		(624,751	)		188,848
			Total liabilities and stockholders' equity	$	879,504		$	954,625	$	106,110		$	1,940,239

See Notes to Pro Forma Combined Financial Statements.

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Notes to Pro Forma Condensed Combined Financial Statements
(dollars in thousands)

(a)

The adjustments reflect the incremental goodwill created as a result of the Thiokol acquisition by Alliant. This is based on our initial allocation of the purchase price and is subject to change pending subsequent valuations. This incremental goodwill will be amortized over 40 years.

Purchase price	$	685,000
Net assets acquired		(615,267	)
Other adjustments (net)		19,713
Incremental goodwill	$	89,446
Annual amortization expense	$	2,236

The other adjustments shown above include transaction expenses, an adjustment to conform Thiokol's revenue recognition policy to ours for certain long-term production contracts and employee-related accruals in connection with severance, retirement and other obligations. An adjustment was also made to accrued liabilities for the employee-related accruals.

(b)

Total interest expense was adjusted to reflect additional interest expense on our new senior credit facilities and the senior subordinated notes and the amortization of deferred financing costs related to our new financing. The actual calculation is shown in the following table. Total interest expense does not reflect interest expense related to the $125 million senior subordinated credit facility we entered into in connection with the Thiokol transaction as we refinanced this facility with net proceeds from the sale of the senior subordinated notes on May 14, 2001.

		Amount		Interest Rate		Interest Expense
Assumed revolver balance year-end (1)		$	3,000	7.25	%	$	218
Tranche A term loans (1)			104,293	8.15	%		8,500
Tranche B term loans			500,000	8.82	%		44,100
Senior subordinated notes			400,000	8.50	%		34,000
	Subtotal new debt		1,007,293	8.62	%		86,818
Amortization of deferred financing fees ($32,998 assumed to be amortized using the effective interest rate method over the scheduled term of the debt)							4,828
Average historical revolver balance for fiscal 2001			71,349	7.25	%		5,173
	Total	$	1,078,642	8.98	%	$	96,819

(1)

Balance gives pro forma effect to the application of the net proceeds of the senior subordinated notes.

(c)

The total income tax provision was adjusted for the effects of the pro forma adjustments. The revised effective tax rates vary from statutory rates principally due to tax effects associated with our business strategies, resolution of tax matters and the impact of state taxes.

(d)

The pro forma combined income statement for the year ended March 31, 2001 assumes that the Thiokol acquisition and related financing occurred on April 1, 2000. We have assumed an early extinguishment of our existing debt and the $125 million senior subordinated credit facility and a portion of the Tranche A term loans, resulting in an extraordinary loss of $15,807, net of a $6,323

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tax benefit, due to the write-off of deferred financing fees and expenses associated with the extinguished debt.

(e)

Net adjustment of cash was determined as follows:

Proceeds from issuance of new debt	$	1,007,293
Repayment of existing debt		(277,109	)
Cost of Thiokol acquisition		(685,000	)
Estimated transaction expenses		(48,463	)
Net application of cash		(1,010,572	)
Net decrease in cash	$	(3,279	)

(f)

The adjustments reflect the $5,342 write-off of deferred charges associated with the refinancing of the existing debt, and recording of $32,998 of new deferred charges paid in conjunction with the financing of the Thiokol acquisition and the issuance of the senior subordinated notes. These deferred charges will be amortized as interest expense assumed to be amortized using the effective interest rate method over the scheduled term of the debt.

(g)

The adjustments reflect the retirement of existing indebtedness and the $125 million senior subordinated credit facilities, and new borrowings related to the Thiokol acquisition, including the senior subordinated notes. The adjustments are summarized as follows:

Retirement of existing debt		$	(277,109	)
Revolving credit facility(1)			3,000
Tranche A term loans(1)			104,293
Tranche B term loans			500,000
Senior subordinated notes			400,000
	Total increase in debt	$	730,184

(1)

Balance gives pro forma effect to the application of the net proceeds of the senior subordinated notes.

(h)

Nonrecurring charges, net of related tax effects, resulting directly from the acquisition are expected to be $5,000 and will be recorded over the 12 months following the date of the Thiokol acquisition.

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PRO FORMA COMBINED FINANCIAL INFORMATION
Notes to Pro Forma Condensed Combined Income Statement