Update:
President of Bangladesh, Abdul Hamid, announced on live television today that Bangladesh Air Force is going to purchase 16 4++ generation multi role fighter aircrafts, 8 attack helicopters and Bangladesh Navy will get 6 next generation frigates built locally in Bangladesh.
My observation :
The frigate contract would most likely be PLAN Type-054A frigates with transfer of technology. AESA radar and multirole VLS system technology would be incorporated from type-052D Destroyer. There were reports that Turkey offered Bangladesh Navy frigates from its MILGEM project but BN rejected it in favour of the type-054A.
For attack helicopters, it would probably be the AH-64. A few pages ago, I posed about BAF negotiating with US for AH-64.
However, there are many Russian websites claiming that BAF has already purchased 8 MI-35M. Previously, BAF has shown interest in Mi-28N, Z-10, T-129 and Mi-35M.
A BAF pilot after test flight of Mi-35.
BAF officials inspecting Z-10.
T-129 was shown in army billboards and in the near future, the army aviation (not the air force) is going to purchase it.
However, the AH-64 is the most probable for BAF out of all these and BAF has been already negotiating recently for these helicopters. Pictured here are Bangladeshi soldiers with an American AH-64.
For fighter jets, I cannot say for sure which aircraft BAF would go for. BAF has not bought any 4th gen fighter jet in the last 20 years so I am not sure which direction BAF will go. Russia's SU-30MKK/MKI based variants seemed to be the top contender for years and so is the MiG-35 but the quality of Russian equipment cannot keep up with its other competitors and hence Bangladesh is not purchasing any major defence equipment from Russia anymore since 2013. Their continued support for Myanmar in the rohingya crisis is also a big factor here. However, there is still a chance they might go for Russian birds.
The Chinese J-10CE has a good chance as the Chinese engines have matured and improved alot, it has AESA radar and has PL-15 which is a game changer. There are also pictures of BAF pilots test flying the J-10. However, along with the Russians, the Chinese also deeply support the Myanmar and provides the backbone of its military.
The Royal Air force has offered Eurofighter Typhoon to BAF in mid 2019. Typhoons would give BAF a major advantage over its regional counterparts but its high price tag means it would be difficult to fit them into BAF budget.
And lastly, there is the F-16. Along with the Ah-64, BAF was also negotiating for fighter jets but no model has been named. BAF would most likely look for F-16 E/F block 60 or F-16V Block 70/72. BAF was previously interested in F-16 in the 1990s but due to security issues, the USA refused to sell the 36 F-16s BAF requested. In recent time, military cooperation between the two countries increased greatly and the US is finally willing to sell BAF its newest F-16 variants. Pictured here are Bangladeshi officials inspecting US fighter jets.