World War II was, indeed, hell — even in the air.

You are reminded of this repeatedly in the stellar new Apple TV series  “Masters of the Air,” (Fridays through March 15) as bomber crews in Boeing B-17 Flying Fortresses — the men of the 100th Bomb Group, aka the “Bloody Hundredth” — are wounded or worse as the United States Air Force strives to gain dominance in the skies over its German counterpart, the Luftwaffe, as D-Day approaches.

The series is the latest World War II-related project from producers Steven Spielberg and Tom Hanks. The director and star, respectively, of the acclaimed 1998 film “Saving Private Ryan” later helped bring to the small screen the highly regarded HBO series “Band of Brothers” (2001) and “The Pacific” (2010), all of which mined great drama from the conflict between the Allied and Axis power that dominated the first half of the 1940s.

“Masters of the Air” does the same, largely under the guidance of John Orloff, who was nominated for an Emmy Award for writing an installment of “Band of Brothers” and who here is the writer or co-writer of every episode.

The series is adapted from the 2006 nonfiction book of the same name by Donald L. Miller.

“Masters of the Air” carries with it a beefy ensemble, which is anchored by stars Austin Butler (“Elvis”) and Callum Turner (“The Boys in the Boat”), who portray Major Gale “Buck” Cleveland and Major John “Bucky” Egan, respectively. Despite their nicknames, the officers have little in common but are the best of friends before each arrives — Bucky before Buck — at the Thorpe Abbotts base in the United Kingdom.

Theirs is the most endearing of bromances. They care deeply about and worry for each other throughout the twists and turns that lie ahead for them in the air and on the ground.

And the performances of the stoic Butler — producers wanted a “John Wayne type” for Buck, according to the show’s production notes — and the cool-and-cocky Turner — a “swashbuckling attitude” was the requisite for Bucky — are two big reasons “Masters of the Air” is so consistently engaging.

While the ensemble also boasts “Saltburn” star Barry Keoghan as another daring pilot, Lt. Curtis Biddick, it devotes more time to two other supporting characters: Major Harry “Cros” Crosby (Anthony Boyle) and Major Robert “Rosie” Rosenthal (Nate Mann).

Cros, who also serves as the series’ narrator, is a navigator with one small problem: He gets pretty sick before he flies. Fortunately, that situation gets resolved when he gets bumped up in rank and bumped down to the ground, during which time the married officer encounters a female British officer, Sandra Wingate (Bel Powley), who seems to be keeping things from him.

The steady-Eddie Rosie, on the other hand, was born to fly, and his sense of duty is part of the reason he flies an incredibly high number of missions.

Although much of its draw is its human drama, “Masters of the Air” doesn’t shortchange you when it comes to aerial sequences, which can be beautiful (smoke trails streaking across the skies), riveting (pilots and crew working to keep a B-17 not only in the air but also en route to its target area) and horrifying (men being ripped to shreds by flak and machine gun fire from enemy fighters) at any moment.

Among the efforts made by the complex production to be convincing was the construction of two B-17 replicas that took nearly eight months to complete, according to the production notes, and came in at 74 feet in length and 9 tons apiece.

You should prepare for the possibility that, given the enormity of the cast, at times you may have trouble keeping track of who is who — especially when the men are up in the air and their faces are largely covered by goggles and masks. Just accept that you’ll know who you need to know well enough as the story unfolds.

As you’d expect — and as you’d hope — “Masters of the Air” leaves you with some information about the real masters of the air and what became of them. That only serves to make you admire them further, as difficult as that is to imagine while you’re watching their fictionalized versions in action serving their country.

“Masters of the Air”

Rated TV-MA, Apple TV+

Grade: A-