October 24, 1986

TWENTY-FIVE years ago this weekend, the New York dancegoer had a choice of four programs to attend. Tonight, 13 companies are performing at theaters around New York City, among them the Joffrey Ballet, which is celebrating 25 years of dance making by its resident choreographer, Gerald Arpino. Things have changed since Mr. Arpino created his first ballet. Jerome Robbins's Ballets: U.S.A. company was on Broadway that weekend in 1961, and Charles Weidman was performing in a downtown loft. But other than that, the pickings were limited to a folk dance and music concert at Carnegie Recital Hall and folk-dancing lessons complete with free tea. Back then, there was no dance season in late October. Today, the dance seasons stretch throughout the year. But there is also more and more varied work to see. This weekend alone, there are three major ballet companies, a wide representation of modern dance styles, a flamenco hit and two tap offerings to choose from. For the adventurous, there are a number of new or unusual performers in theaters far off the beaten track, and even a Sex and Dance festival.

The Manhattan District Attorney is investigating allegations that the former commander of the largest National Guard organization in the country improperly intervened on behalf of a private company that sold equipment to the unit, according to officials familiar with the investigation. The officer, Maj. Gen. Bernard G. Ehrlich, a partner in Biaggi & Ehrlich, a law firm associated with Representative Mario Biaggi, Democrat of the Bronx, was ousted Wednesday as commander of the 42d Infantry Division of the New York Army National Guard because of what state officials called a breach of the military code of conduct. Maj. Gen. Lawrence P. Flynn, Governor Cuomo's chief of staff and the commander of the state militia, has declined to elaborate his reasons for dismissing General Ehrlich.

Friday A '34 CAR, GOOD AS NEW For $3,500 this weekend you can buy a 1934 Duesenberg four-door convertible. Made of wood. Three feet long. It is one of the items for sale at Crafts Park Avenue, a bazaar-exhibition at the Armory on Park Avenue between 66th and 67th Streets that opens today. The model car, built to scale, sports spoked wheels and a detailed chassis. Those interested in more functional crafts may choose from surrealistic sculpture clocks, sushi dishes and chopsticks made from exotic hardwoods, handblown glass lampshades, and belts and bags made from leather and snakeskin. These and other creations represent the work of the more than 200 artisans participating in the exhibition. The show is open today from 5 to 9 P.M.; tomorrow from 11 A.M. to 9 P.M., and Sunday from noon to 7 P.M. Admission is $4 today, ($5 for both Saturday and Sunday.) Information: (914) 679-7277.

Hasenfus Cites Secret Field Eugene Hasenfus said a plane carrying supplies for Nicaraguan rebels used a clandestine airstrip in Costa Rica this year.

Orders to American factories for durable goods such as heavy machinery, aircraft and transportation equipment as well as for large household appliances jumped 4.9 percent in September, the largest rise in nearly two years. Although the Reagan Administration was quick to seize on the report as a sign that the sluggish economy was picking up steam, some private economists suggested that the surge in orders was primarily the result of a scramble by companies to make their purchases under the current tax law. The tax revision measure signed Wednesday by President Reagan will provide less favorable treatment for some types of machinery and equipment purchased after Dec. 31. Mr. Reagan, campaigning in the Middle West for Republican Senate candidates, hailed the Commerce Department report as a sign that the economic picture was looking brighter. ''What this means is more production and more jobs in the future,'' he said.