Even with F-16s, Ukraine's pilots still wouldn't be 'out of the woods' against Russia's air force, US officials say

• NATO members Poland and Slovakia have pledged to send Ukraine more MiG-29 jets.
• Ukraine is still seeking to get Western-designed jets, particularly the US-made F-16.
• F-16s have specific needs, and Russia could still bring them down, officials and experts say.

Poland and Slovakia are sending their Soviet-designed MiG-29 fighter jets to Ukraine, promising to give Kyiv a bit of the airpower boost it has long sought. Ukrainian leaders are still seeking Western-made jets, but delivering those aircraft and preparing Ukraine to use them would require considerable training and maintenance — and they wouldn't overcome the challenge posed by Russia's aircraft and air defenses, officials and experts say.