when do Delta airlines summer sales start

Delta airlines will start its international flights to cities in Asia and Europe for spring and summer 2011, continuing its focus on markets with high demand for business travel.
our 2011 schedule reflects a measured response to business customers' desire for increased access to the world's most important business capitals. New flights to China, London's Heathrow Airport and increased flights to our international alliance partners' gateways at Paris Charles de Gaulle, Amsterdam Schiphol and Guangzhou are cornerstones of our international plan for 2011."
Business Class to Europe at leisure prices $1,469–$3,329

Round-trip sale fares for travel from Amsterdam, Netherlands to Miami, Florida
€619
delta airlines domestic flights summer sales Each-way Fares*
based on round-trip purchase Purchase By
Atlanta flights to select US cities $54-$139 Apr 14
Detroit flights to select US cities $84-$154 Apr 14
Detroit flights to select cities in Europe $379-$519 Apr 18
Atlanta flights to select cities in Europe $389-$529 Apr 18
New York flights to select cities in Europe $289-$479 Apr 18

Between Atlanta, GA (ATL) and: Each-way Sale Fare**—round-trip purchase is required
Akron, OH (CAK) $99
Baltimore, MD (BWI) $79
Baton Rouge, LA (BTR) $99
Bloomington, IL (BMI) $99
Boston, MA (BOS) $94
Brunswick, GA (BQK) $79
Buffalo, NY (BUF) $104
Charlotte, NC (CLT) $54
Chicago-Midway, IL (MDW) $79
Chicago-Ohare, IL (ORD) $79
Cincinnati, OH (CVG) $89
Dallas-Fort Worth, TX (DFW) $94
Dayton, OH (DAY) $89
Daytona Beach, FL (DAB) $99
Denver, CO (DEN) $124
Detroit-Wayne County, MI (DTW) $79
Flint, MI (FNT) $79
Greensboro, NC (GSO) $69
Gulfport, MS (GPT) $74
Indianapolis, IN (IND) $69
Jacksonville, FL (JAX) $64
Key West, FL (EYW) $114
Killeen, TX (GRK) $124
Lewisburg, WV (LWB) $79
Manchester, NH (MHT) $119
Melbourne, FL (MLB) $99
Memphis, TN (MEM) $59
Miami, FL (MIA) $79
Milwaukee, WI (MKE) $79
Moline-Quad Cities, IL (MLI) $124
Orlando, FL (MCO) $79
Pensacola, FL (PNS) $59
Philadelphia, PA (PHL) $79
Phoenix, AZ (PHX) $134
Pittsburgh, PA (PIT) $79
Portland, ME (PWM) $124
Providence, RI (PVD) $119
Raleigh/Durham, NC (RDU) $59
Rochester, NY (ROC) $79
San Antonio, TX (SAT) $94
Sarasota, FL (SRQ) $79
Savannah, GA (SAV) $104
South Bend, IN (SBN) $139
St. Louis, MO (STL) $79
Tampa, FL (TPA) $79
Valdosta, GA (VLD) $79
Washington-Dulles, DC (IAD) $99
Washington-Reagan National, DC (DCA) $99
West Palm Beach, FL (PBI) $79

Origins and Destinations Sale fares between Atlanta, GA and select U.S. cities.
Fares $54-$139* each-way, round-trip purchase is required.
Purchase by April 14, 2011
Travel Period Travel must be completed by November 2, 2011.
Advance Purchase and Minimum Stay 10 days; Saturday night