(Reuters) - Defense contractor General Dynamics Corp missed Wall Street estimates for quarterly profit and revenue on Wednesday, as its aerospace unit delivered fewer Gulfstream jets due to the COVID-19 pandemic, but 2021 revenue guidance sent shares up nearly 4% in early trading. During a post earnings conference call Phebe Novakovic, the General Dynamics CEO, said she expected 2021 revenue to be up $1 billion to $39 billion and forecast earnings share in the range of $11.00 to $11.05 per fully diluted share. The 2021 outlook counteracted investor disappointment that quarterly Gulfstream jet deliveries declined to 40 units from 44 a year ago, which sent shares down slightly in early trading. Business jet deliveries in 2020 were hampered by coronavirus shutdowns, making it harder for defense contractors like General Dynamics to deliver jets due to COVID-related travel restrictions and factory slow-downs. Sales in the company’s aerospace unit posted a 16.9% fall to $2.44 billion. Total revenue fell 2.7% to $10.48 billion. However, the broader business jet market saw an order boost late in 2020 as U.S. buyers rushed to take advantage of favorable tax rules they feared could change under the new Biden administration. During the quarter, General Dynamics’ marine systems unit, which makes ships and submarines for the U.S. Navy, was awarded a $9.47 billion contract for the construction of Columbia class submarines, moving the U.S. Navy’s top procurement priority out of the early-construction phase. The shift to the construction phase for the first two Columbia class submarines added to General Dynamics’ backlog which sat at record-high $89.5 billion at the end of the year. Net earnings fell to $1 billion, or $3.49 per share, in the fourth quarter ended Dec. 31, from $1.02 billion, or $3.51 per share, a year earlier. Analysts on average expected earnings of $3.54 per share on a revenue of $10.78 billion, according to Refinitiv data.