They were flying a recon mission out of Port Moresby and some seven hours into the mission were directed to return to Dobadura due to weather at Port Moresby. Fighter Sector Command was tracking an aircraft in the Huon Bay area when it disappeared off the scope. This was assumed to be Jack Volz's aircraft. Search was made but no sign of the aircraft then or later. It was gone. 
(Wood, Wiley; Legacy of the 90th Bomb Group; page 70)

SSgt. Berthold Allen Chastain was officially declared dead on 28 October 1944.

The Pilot and Crew of the "Shack Rat" at the time of its disappearance were:

Berthold Allen Chastain was posthumously awarded the Purple Heart, which was presented to his family. Later, President Lyndon B. Johnson issued to Berthold's daughter, Tulie Mae Chastain-Swilling, and to Berthold's mother, Estella Mae Hensley-Chastain, presidential citations for bravery for Berthold Allen Chastain's ultimate sacrifice on the altar of Freedom. The citations and Purple Heart are now in the possession of Berthold's grandson, Ralph Stephen Swilling, who resides at the Eastern Band of Cherokees' Qualla Boundary in North Carolina. Steve is one of five children born to Berthold's daughter, Tulie Mae Chastain-Swilling, and her husband Thomas Winfrey Swilling. Berthold's grandchildren, in order of birth from oldest to youngest, are Thomas Allen Swilling, Danny Lamar Swilling (deceased), Ralph Stephen Swilling, Cherie Yvette Swilling-Childs, and Tina Claudette Swilling-Falkowski.

Berthold, his brothers, his daughter, his five grandchildren, and his eight great grandchildren have always held love for Creator; love of family; and love for Freedom, Liberty, Equality, and Democracy as blessings and sacred trusts bestowed upon us by Creator, all of which are preserved at great cost. Berthold's poetry reflects the principles that he held most dear. His service to his country reflected the depth of his convictions to preserve those principles for his family and all who cherish these values.

No one knows better the price of Freedom than the families of those who paid for it with their lives in battle. As the grandchildren of Berthold Allen Chastain, my siblings and I often gazed at the oval frame that always hung on the living room wall containing the sepia toned photo of our grandfather dressed in his flight gear, ammunition belt draped across his chest, holding a .50 caliber machine gun at port arms, and wondered what it would have been like to have known this man—this family icon—this warrior with the kind face. My brothers and sisters and I saw him as a standard against which to measure our own lives; and our father's strength and character reinforced that standard. As the firstborn, and as the oldest son in our family, I enlisted in the Marine Corps and served in the 2nd Marine Air Wing as a door gunner and crew member on a chopper during the Vietnam era. I was not drafted, as many were at that time. I volunteered. Because of the sacrifice my grandfather made to preserve our Freedom and Liberty, in hopes that Justice and Equality for our people would someday follow, I saw it as my duty to do my part to defend and preserve those rights for my family, children, and grandchildren yet to come. To do less would have been to dishonor the sacrifice my grandfather made willingly for my sake.

Berthold Allen Chastain not only inspired a deep sense of patriotism and pride in our family, but also the value of family, helping our friends and neighbors, and defending the rights of all who seek Freedom, Liberty, Justice, and Equality. These words are capitalized, because they are more than mere words. They are, in fact, entities with lives of their own; lives born from our hearts' deepest yearnings and sustained by the blood sacrifices of those who die in their names. Freedom, Justice, Equality, and Liberty are the things most longed for and the gifts most precious; but sometimes they are the gifts most taken for granted until the time for sacrifice comes again and it is our family that is called upon to lay the life of a loved one upon the altar. I pray that the family of Berthold Allen Chastain and the families of the warriors who were the Shack Rat's pilot and crew will never take Freedom, Liberty, Justice, or Equality for granted but will continue to fight with all we have to preserve those rights and strive toward their perfection.

Wado, Ududu'.
Thank you, Grandfather.