I loved the UI, the newspaper, the fonts, everything was extremely well presented. I just had no real idea what I was doing, I thought i was opening the oxygen pretty far but ran out of air haha. Very well done!

The game is very well designed. Good job!

I like the cinematic menu background, the menu UI being a newspaper.

It is nice that each interactive object has a label. However the procedure itself is not clear.

The clouds look really weird but I guess it's difficult in 3 dimentions.

Managed to find the barometer on the table next to the book where observations are logged. 

But some other things seem to not function - the oxygen cylinders are only two. But when the second one got emptied the notification informed me to open the next one?! Is there a way to refill the cylinders?

Followed Pablo V’s advice and played in Firefox w/o a problem. I played more than a few times and had a good time doing it. Your controls and feedback were super intuitive after figuring out the 1st one. The audio is eerie and creates a tense and lonely sense of solitude. I loved that all the dials and feedback were legit – the barograph actually recording my janky trek skyward was cool. I died a couple times, I landed a couple times, I feel like my duty was done and I contributed to the pursuit of the thin air above.

Played in browser (firefox) with no apparent issues in my case...
Impressive visuals, with moving shadows as the balloon ascends, everything is there and everything has a good reason to be there. At first I thought the meters were just static, I coudn't believe how good they do react. It really made me feel inside. SFX are amazing, clock sound is 3D!! (probably other sounds too, didnt check). Mechanics feel very organic. I tried a couple of times and always got a "burst in the stratosphere", but I got a lot of fun. I clearly need to fully understand how to pilot that thing, so I will keep trying. 
Despite taking place before what is actually considered the space race, you really delivered an amazing scope for such a short time, congrats.

The browser struggled initially, but what a game once downloaded!

Spectacular visuals, from the opening to the cloud view, to the locks on the overhead hatch. The experience was nerve wracking but bursting with exploration and consistent tension. Superb SFX (especially the hatch and the ballast pump).

But my favourite part was the clever mouse mechanics one the valve and the writing. Hats off!

Not sure if this strictly adheres to the jam theme. Ignoring that, it is a very well executed first person 3D simulation of a 1930s balloon flight. I kept dying due to not being able to follow the popup instructions in time. They don't stay on screen very long either. I made 3 attempts which all ended in failure (= death). I got as far as needing to wind the barograph. I have no idea what a barograph is and I could find it anywhere.

I didn't realise WASD could be used to move around (tricky for me being left handed) so maybe that helps find it.

Still, I laughed at my incompetence each time I died which is the sign of a good game (blaming yourself instead of the game for failure).