Textron Inc. reported that 1979 profits increased about one percent from 1978 levels on a 6.3 percent rise in sales.

Increased sales of consumer products and machine tools and an improved aerospace product mix were offset by weaknesses in the automotive, truck, construction and some consumer markets, Textron Chairman Robert P. Straetz said.

Earnings for the year were $169.8 million ($4.51 a share) on sales of $3.392 billion compared with $168.07 million ($4.47) in 1978 on sales of $3.23 billion.

For the final quarter, Textron earned $43.65 million ($1.16) on sales of $878 million compared with $45.31 million ($1.20) a year earlier on sales of $907.39 million.

Citing a 50 percent increase in the cost of fuel Pan American World Airways reported a loss of $12.9 million in the fourth quarter of 1979 compared with a $4.6 million loss in the same period of 1976.

For the year, Pan Am earned $76.1 million, down from $118.8 million in 1979, on a 12.7 percent increase in operating revenues. The 1979 results include an $18 million gain on the disposal of equipment compared with a $14.7 million similar gain the previous year.

William T. Seawell, chairman and chief executive, said airline traffic weakened slightly in the fourth quarter "but the overwhelming problem . . . was the great increase in the cost of fuel and the lack of fare relief from government agencies."

Operating revenues for the year were $2.5 billion, up 12.7 percent over 1978. Operating expenses, led by a 50.5 percent increase in fuel costs, rose 17.1 percent to $2.4 billion. Per-share earnings were $1.07 in 1979, down from $2.31 in 1978 on an increased number of shares outstanding.

Pan Am said accounting changes at yearend "had a substantial favorable impact on the fourth-quarter results," including a write-off on the cost of its successful effort to acquite National Airlines and settlement of a large insurance claim in connection with a 1977 aircraft loss.

The merger with National became effective last month after a long battle involving bids by Eastern Air Lines and Texas International.

"Without these and other entries relating to periods prior to the fourth quarter, the results for the quarter would have been approximately $36 million worse than the 112.9 million loss," the company said.

Seawell said he was encouraged by recent Civil Aeronautics Board action on fares, "but a large gap (between fares and costs) exists and it will be some time before the imbalance will be remedied even if the board takes further action. We do not begin 1980 under favorable circumstances, but we hope to see improvement during the year."

McGraw-Hill Inc., the publishing combine, earned $3.10 a share last year, up from $2.57 in 1978, as both advertising revenues and periodical sales boomed.

Net income rose to $76.9 million on sales of $879.88 million from $63.66 million in 1978 on sales of $761.2 million.

Fourth-quarter profits were $21.87 million (88 cents a share) on sales of $262.75 million compared with $18.99 million (77 cents) a year earlier on sales of $219.43 million.

Chairman Harold McGraw said the 15 percent earnings gain for the year reflected strong performances by all McGraw-Hill operations. Business Week magazine did particularly well. The book business was good in the United States but somewhat disappointing abroad. Stanley & Poor's statistical and rating service also did well, as did F. W. Dodge Co. and the other data branches.