* Apple climbs 4 percent after earnings
* GE posts 80 percent rise in profits, raises dividend
* Futures up: Dow 66 pts, S&P 8.6 pts, Nasdaq 26.75 pts
By Chuck Mikolajczak
NEW YORK, April 21 (Reuters) - U.S. stock index futures rose on Thursday, putting the S&P 500 on track for its first weekly gain in the last three, as strong corporate earnings and outlooks generated optimism about the economic recovery.
* Apple Inc climbed 3.9 percent to $355.90 after its results beat Wall Street's expectations as iPhone and Mac computer sales scaled new heights while iPad supplies could not keep up with global demand.
* Wireless chip maker Qualcomm Inc posted better-than-expected quarterly results and raised its full-year financial targets on improving demand for advanced phones.
* General Electric Co advanced 3.7 percent to $21.15 after the largest U.S. conglomerate reported an 80 percent surge in first-quarter profit and raised its quarterly dividend.
* S&P 500 futures added 8.6 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures gained 66 points and Nasdaq 100 futures rose 26.75 points.
* DuPont's quarterly profit rose 27 percent due to strong sales of electronic and solar materials, leading the chemical giant to boost its earnings forecast.
* Fellow Dow component Travelers Cos Inc reported a 30 percent rise in quarterly profit as the largest publicly traded U.S. property insurer saw an increase in investment income.
* Hamburger chain McDonald's will also report earnings, with the market's focus likely to be on its power to raise prices as food and fuel costs climb. Analysts expect a 2 percent rise in March sales at established U.S. restaurants.
* Morgan Stanley, the second-largest U.S. investment bank, is also on tap to report earnings.
* Economic data due on Thursday includes weekly jobless claims at 8:30 a.m., while leading indicators for March, February home prices and the Philadelphia Fed's index of business conditions for the mid-Atlantic region for April are expected at 10 a.m..
* Volume is expected to remain light on Thursday ahead of the extended holiday weekend. U.S. markets are closed on Friday in observance of Good Friday.
* European shares advanced for a third straight session to hit a one-week high, with a raft of forecast-beating company results improving market sentiment and boosting chemical and technology stocks.
* Asian stocks jumped as investors scrambled for higher-yielding assets, particularly in emerging markets.
* Big earnings surprises gave a positive turn to investor sentiment on Wednesday, propelling U.S. stocks to their best day in a month and lifting the Dow industrials to their highest in almost three years. (Reporting by Chuck Mikolajczak; Editing by Kenneth Barry)