In fact, a main piece of evidence that is cited in the document points to an attack that was executed by individuals on the ground, not from an aircraft, on the morning of April 4. This conclusion is based on an assumption made by the White House when it cited the source of the sarin release and the photographs of that source. My own assessment, is that the source was very likely tampered with or staged, so no serious conclusion could be made from the photographs cited by the White House.
However, if one assumes, as does the White House, that the source of the sarin was from this location and that the location was not tampered with, the most plausible conclusion is that the sarin was dispensed by an improvised dispersal device made from a 122 mm section of rocket tube filled with sarin and capped on both sides.
The only undisputable facts stated in the White House report is the claim that a chemical attack using nerve agent occurred in Khan Shaykhun, Syria on that morning. Although the White House statement repeats this point in many places within its report, the report contains absolutely no evidence that this attack was the result of a munition being dropped from an aircraft. In fact, the report contains absolutely no evidence that would indicate who was the perpetrator of this atrocity.