New Orleans , Louisiana ( CNN ) -- A dual-pronged effort to stop the oil gushing from BP 's runaway well in the Gulf of Mexico shows promise for this weekend , the head of the government 's response team said Friday . But things are likely to get worse before they improve . Late Friday , Retired Coast Guard Adm. Thad Allen said in a statement that he and Energy Secretary Steven Chu had approved BP 's plan to install an oil-recovery vessel , the Helix Producer , at the same time that a new cap is placed over the well , `` which will require temporary suspension of the current top-hat containment system . '' During the seven to 10 days that it will take to switch the caps , the 15,000 barrels of oil that the Discoverer Enterprise ship has been collecting daily are expected to flow unimpeded into the water , he said . Allen said he approved the plan in order to take advantage of favorable weather predicted for coming days and because , once the switch is complete , the resulting capacity to contain oil `` will be far greater than the capabilities we have achieved using current systems . '' BP spokesman Mark Proegler called it the `` capping stack , '' which he described as a larger , better-fitting seal than the one currently covering the well . The latter cap `` can be removed quite quickly '' and BP will start replacing it with the `` sealing cap '' on Saturday , he said . If successful , the operation could halt the gushing that started April 20 after an explosion that killed 11 people on the Deepwater Horizon in the Gulf . But any such fix would be temporary , he said . The permanent solution would still be completion of a relief well , he added . Scientists have estimated 35,000 to 60,000 barrels of oil are spewing daily from BP 's breached Macondo well . They have been basing their estimates on high-resolution video and data from acoustic devices used to measure density . But Allen said that , once the long-term containment cap is in place , scientists will for the first time have the empirical data they need to determine the true flow rate . `` I would think once the capping device is on , we would get the most accurate flow rate to date , '' he said . Switching the containment cap could increase the amount of oil collected each day to 60,000 to 80,000 barrels , Allen said . Under a new alignment , four vessels would participate in oil recovery , one more than the three currently involved . In a separate advance , federal responders expressed optimism Friday about a new aerial weapon in their arsenal . A 178-foot U.S. Navy blimp , the MZ-3A , was flown from New Orleans to Mobile , Alabama , to be used to survey the disaster area as soon as Saturday , depending on the weather . Officials said they hope surveys from the blimp will help them cut the time needed to get skimmers to the scene of oil slicks . `` Having something at a low altitude that can stay on scene a very long time is extremely valuable , '' Allen said . `` We are anxious to see how it works . '' The first relief well BP is drilling in the Gulf of Mexico could intercept the leaking Macondo well in seven to 10 days , Allen said Thursday . But the time it will take to seal the well will depend on `` where the oil is coming up through , where they can intercept , where they can put the mud in , where they can put the cement plug , '' he said . Also Friday , the president 's Oil Spill Commission said it is hiring Richard A. Sears , a deepwater drilling expert with 30 years of experience in the oil and gas industry and academia , to serve as its science adviser . The commission , comprising seven members appointed by President Barack Obama , will hold public meetings Monday and Tuesday in New Orleans . It is charged with determining the causes of the Deepwater Horizon disaster and recommending changes in policies and law to prevent any such future calamities . Commission spokesman Pete Nelson said the commission is also hiring Jay Hakes as its research director . Hakes , an alumnus of the Carter administration , served as director of the Jimmy Carter Presidential Library and Museum and headed the Energy Information Administration at the U.S. Department of Energy during the 1990s . CNN 's Sanjay Gupta , Vivian Kuo and Aaron Cooper contributed to this report .
Monday : Allen and Chu approve BP plan to replace caps . Plan : switch will take 7 to 10 days during which oil will flow unimpeded . Oil spill commission appointed two new experts . Work on replacing the cap is to begin Saturday .