Megan,
A Model Chinooks have a "sharp" tail fin.....B Model and forward have the "Square" tail fin.
Unless my old eyes are lying to me the Chinook in the video appears to be not an A Model....for what it is worth in the 75 Squadron video.
The reason for the design change was by squaring the tail fin it provided a real improvement in yaw stability....something akin to adding over thirty feet of Fin to achieve the same improvement.
It was among the best improvements in handling that has been made. The A Model was very lively in yaw.....with two Rotor Heads arguing about which was going to lead in the dance.
I believe the RAAF started with C models and then progressed to D's and F's.
I would give three feet of my Trigger Finger to have flown the MH version of the Chinook with all of its capability with the F Model probably. being a real Horse to ride as. well.
From Wiki....
The
Australian Defence Force has operated
Boeing CH-47 Chinook heavy-lift helicopters for most of the period since 1974. Thirty four of the type have entered Australian service, comprising twelve CH-47C variants, eight CH-47Ds and fourteen CH-47Fs. The helicopters have been operated by both the
Royal Australian Air Force (RAAF) and
Australian Army.
An initial order of eight Chinooks for the RAAF was placed in 1962, but soon cancelled in favour of more urgent priorities. The Australian military still required helicopters of this type, and twelve CH-47C Chinooks were ordered in 1970. The CH-47s entered service with the RAAF in December 1974. The eleven surviving Chinooks were retired in 1989 as a cost-saving measure, but it was found that the Australian Defence Force's other helicopters could not replace their capabilities. As a result, four of the CH-47Cs were upgraded to CH-47D standard, and returned to service in 1995 with the Australian Army. The Army acquired two more CH-47Ds in 2000 and another pair in 2012. The CH-47Ds were replaced with seven new CH-47F aircraft during 2015, and another three were delivered in 2016. A further four CH-47Fs were ordered in 2021, with two being delivered that year and two others arriving in 2022.