Charles Brown has always loved flying. He loves the steady roar of the engine beneath him as the plane rises high above a shrinking ground, turning houses into small blocks of color and cars into floating specks of light below.

Mr. Brown’s passion evolved from building model airplanes as a child to training in aviation ordnance when he joined the U.S. Marine Corps in 1985. His military career was cut short a year later, when he hit his head diving into a swimming pool and injured his spinal cord, resulting in incomplete paralysis of his arms and legs.

He now uses a wheelchair and, because of his disability, finds flying to be a risk.

“When I fly nowadays, it literally is a moment of, ‘OK, what do I have to do to get through this day without getting injured more?’” Mr. Brown explained.

On his first flight after his injury, Mr. Brown got a concussion during the landing; he couldn’t stay upright, and his head slammed into the seat in front of him. On another flight a few years ago, two airline employees dropped him — it was a hard fall — while lifting him into a special aisle wheelchair. He shattered his tailbone and spent four months in the hospital afterward, battling a life-threatening infection.

There’s also the worry of what will happen to his $41,000 wheelchair when it is loaded and unloaded from the plane. The wheelchair, custom designed to fit Mr. Brown’s body, prevents pressure sores. Without it, he could risk another potentially life-threatening infection.

It’s not uncommon for airlines to lose or damage wheelchairs. In 2021, at least 7,239 wheelchairs or scooters were lost, damaged, delayed or stolen on the country’s largest airlines, according to the Air Travel Consumer Report. That’s about 20 per day.

Because of these risks, many people who use wheelchairs say flying can be a nightmare.

Even on a flight that goes smoothly, Mr. Brown endures multiple indignities from the moment he arrives at the airport to the moment he leaves, he said, largely because of a lack of accessibility for people with disabilities.

Much of this could be avoided, he and other advocates argue, if airplanes and airports were designed to accommodate passengers who use wheelchairs. And while the Department of Transportation recently published a bill of rights for passengers with disabilities, the initiative was a summary of existing laws and did not expand the legal obligations of the airlines.

To get a firsthand glimpse of the difficulties faced by passengers who use wheelchairs, The New York Times documented Mr. Brown’s experience on two recent American Airlines flights from Palm Beach to San Antonio, with a connection in Charlotte, N.C. Here’s a step-by-step visual diary of what we saw.

Check-in and security

Mr. Brown arrives and meets his travel companion outside the Palm Beach International airport at 7:25 a.m., three hours before his first flight of the day. (He usually arrives early, he said, because every step of the process takes longer for him.) As he makes his way inside, he stops to fist-bump the airport employees who bring his luggage to the check-in counter. Mr. Brown, the president of the Paralyzed Veterans of America, flies frequently for his job and has befriended several Palm Beach airport employees, who are intimately familiar with his needs.

Most check-in counters tower above Mr. Brown, who must lean across the luggage scale to tell an employee that his custom wheelchair weighs 416 pounds — information that he already filled out on a form when he booked his ticket last week. Mr. Brown also checks a shower wheelchair, a medical bag and a second bag of luggage.

The security line, a snake of belt barriers that Mr. Brown bypasses because he cannot easily go through it, is quiet and completely empty this morning.

Mr. Brown gets personally screened by a Transportation Security Administration agent every time he flies. He stretches his arms out as an agent pats him down, running his hands along Mr. Brown’s back, collar, arms and thighs. The agent then swabs his hands, shoes, thighs, the back of his chair and the chair headrest for substance testing.

Today, Mr. Brown said, the agent did a good job. In the past, he has had agents who demanded he lift his legs or lift his body so that they could pat his butt — both actions that Mr. Brown cannot perform because of his disability. Once, after complying with two full-body pat-downs, Mr. Brown got an impossible request from an agent.

“They said, ‘Now I need you to stand up.’ I said, ‘That ain’t happening,’” Mr. Brown recalled. He had to call for a supervisor to resolve the situation.

Roughly 40 minutes after Mr. Brown arrived at the airport, he reaches his gate. He drinks some water and takes his medication.

Normally, Mr. Brown says, he would not drink water before a flight, because many airplane bathrooms are inaccessible to him. Planes with two aisles are required by the U.S. Department of Transportation to have at least one accessible bathroom on board, but planes with only one aisle — which have been used more frequently for long-haul flights in recent years — are not required to have an accessible bathroom.

Today is an exception to Mr. Brown’s no-water rule, though, because he recently had a kidney stone. Because he cannot use the bathroom on the plane, he is using a Foley catheter — which can increase his risk of getting hurt when he is carried and transferred by employees.

On previous flights, Mr. Brown has had to go to the bathroom into a bottle as he sat in his airplane seat, with blankets thrown on top of him, he said.

Boarding the plane

More and more passengers arrive at the gate, some of them consuming snacks or packaged breakfasts. Mr. Brown refrains from eating; he can’t risk needing to use a bathroom on the flight. He hasn’t eaten anything since 1 p.m. yesterday.

Forgoing food and water for hours before a flight is a common practice among travelers who use wheelchairs and cannot access the bathroom.

When it’s time to board, Mr. Brown must again tell airline crew members how heavy his chair is and how many people he needs to lift him onto an aisle chair — a special, small wheelchair that can fit into an airplane’s narrow aisles.

He repeatedly asks one crew member to put his wheelchair’s headrest into his suitcase and goes over instructions on how to fold up and stow his wheelchair safely. The crew member doesn’t seem to understand him, and eventually someone else steps in to help.

Mr. Brown enters the jet bridge before any other passengers. This gives him privacy during his transfer onto the plane — the part of traveling he worries about most. One drop or slip could mean serious injury.

Today, two managers are watching. This is unusual, he said. He tucks in his Foley catheter and raises his arms in anticipation. On the count of three, one airport employee grips his chest and the other lifts under his thighs to smoothly shift him into an aisle chair. In midair, Mr. Brown’s legs begin to spasm.

Mr. Brown is wheeled, backward, 13 rows to his seat, then positions himself for another transfer. His arms and legs dangle for a moment — during which he watches an armrest graze under his thighs and braces himself for any possible outcome — before he is safely put down again on a special cushion he uses to help prevent pressure sores when he flies.

In the air

During the two-hour flight, Mr. Brown jerks with movement every minute or two. His legs splay outward, spilling his right knee into the aisle and causing his hips to hurt. (He always gets assigned a seat by the aisle, not the window, because it’s easier for crew to lift him into those seats.) In his custom wheelchair, there are pads to hold his legs in place. On the airplane, the best substitute he has are his hands, which he constantly uses to readjust his legs and push them inward. By the end of the flight, he rates the pain level in his hips as a 2 or 3 out of 10, comparing it with a nagging headache.

Just before landing, Mr. Brown rams his right arm against the seat in front of him and presses with effort as the plane lands with a thud. He is trying to stop his head from lurching forward into the hard plastic seat.

It was a harsh landing — the kind a pilot in the Navy or Marine Corps would probably make, he says with a smile, but definitely not someone from the Air Force.

As other passengers leave the plane, suitcases and bags of all sizes and colors roll past Mr. Brown, some occasionally hitting his knee. He and his travel companion are the last to deplane; they’re waiting for airline crew to bring his custom chair to the jet bridge — something that airlines are required to do if passengers have requested it.

Mr. Brown doesn’t want to leave his seat and get into an aisle chair until he knows his custom wheelchair is ready for him at the jet bridge; if he spends more than 20 minutes in an aisle chair, he says, he’s likely to get pressure sores. Sometimes, though, he has been forced to sit in an aisle chair for nearly an hour while he waits for crew to find his wheelchair.

Exiting the plane

Cleaning crews have already come through — vacuuming, wiping down seats and picking up trash. Airline crew repeatedly ask Mr. Brown if he will get off the plane, even though his chair isn’t ready. The staff are under pressure to board the plane for the next flight. Eventually he relents, even though his custom chair still isn’t ready.

The two gentlemen lifting Mr. Brown for the transfer out of his airline seat seem hesitant, as if they’re afraid to hurt him. He tries to tell them to hold onto him tightly and reflectively takes a defensive position, tucking his shoulders and hands inward to protect himself.

The workers don’t quite lift him high enough, causing him to bump the raised armrest and be partially dragged into the aisle chair, landing with a dull thump. The straps on the chair to hold his feet in place don’t seem to be working properly, so a crew member refastens them three times.

Mr. Brown is pushed out of the jet bridge in front of a crowd of passengers waiting to board the plane for the next flight, which is now boarding later than expected. Some look exasperated, others tired; many are staring at him. As he wheels past, one stranger mutters, “Chaos.”

About 10 minutes later, employees bring Mr. Brown’s custom chair to the gate and start transferring him in front of a crowd of passengers.

“It’s frustrating,” he says. “I’m not going to say ‘embarrassing’ anymore because I’m just over that. But it is kind of embarrassing, especially if your pants are hanging off your bottom.” He’s had his pants fall down during public transfers before.

This time the men switch places, with the stronger man lifting Mr. Brown’s chest. They complete a better transfer. An airline worker at the check-in counter soon notices the commotion and comes over to apologize to Mr. Brown about the lack of privacy.

A layover and a connection

Mr. Brown has a two-hour layover in Charlotte and is supposed to board his 2:45 p.m. flight to San Antonio, which is scheduled to land at 4:42 p.m. As he waits, his stomach is starting to get “shaky,” he says.

Just before the flight is supposed to board, the gate agent announces that there is a delay. The flight will now depart at 4:30 p.m. and land at 6:30 p.m. But, with the time it takes to deplane and get to his hotel, Mr. Brown doesn’t think he can make it until after 8 p.m. to eat again.

At 2:16 p.m., he finally bites into a Snickers bar. It has been 25 hours since his last meal. Just before he boards his next flight, Mr. Brown also eats a cup of pretzel bites from Auntie Anne’s and strikes up a conversation with a fellow Marine who’s waiting at the gate. They trade stories and discuss where they were stationed.

As the flight prepares to board, airline crew wheel three elderly women on regular airport wheelchairs — the type of chair intended for use by those who can’t walk long distances — down the jet bridge to board the plane first. Then, regular passengers start to crowd around the check-in gate. A family with a baby stroller checks in and starts walking to the jet bridge. Amid the commotion, Mr. Brown seems to have been forgotten entirely.

Mr. Brown starts to get upset with the check-in agents. The Department of Transportation stipulates that disabled passengers who need additional time or assistance to board the airplane must be allowed to board first. Further guidance says that, if possible, airline crews should avoid transferring someone from an aisle seat to a plane seat in front of other people.

Soon after he complains, Mr. Brown is quickly wheeled down the jet bridge, shaking his head in frustration and disbelief at a supervisor who insists she did nothing wrong.

In preparation for his second flight, two men strongly and swiftly transfer him to his aisle chair and then to his seat in a blur of motions that leaves Mr. Brown breathing heavily afterward.

Mr. Brown’s body becomes a physical hurdle of sorts for another passenger who tightly squeezes past him and steps over his legs to get to the window seat. (His travel companion was seated between them.) Mr. Brown looks uncomfortable, but, unable to move out of the way, he’s stuck.

He tries to nap on the second flight but has to rouse himself from his sleep to shove his legs back into a straight position and stop his knees from poking out.

The second landing is smoother, but the plane still rattles and shakes as it slows down. Mr. Brown’s arm is once again outstretched against the seat in front of him as he tries to hold himself steady, but there’s a shake of exhaustion in his elbow now.

People start deplaning at 6:50 p.m., and one person thanks Mr. Brown for his service on the way out. Mr. Brown nods and pushes his knee in as people walk by, trying to avoid being bumped by suitcases. Soon after the plane empties, a crew in bright yellow vests starts to clean up around Mr. Brown.

At 7:10 p.m., his custom chair is ready for him in the jet bridge. Mr. Brown has another smooth transfer onto the aisle chair, but he is placed down a little crooked, so an airline crew member has to hold his knees to make sure they don’t bump every seat on the way out.

Amy Lawrence, a spokeswoman for American Airlines, said in an email that the company is focused on ensuring a positive experience for those with disabilities.

In response to complaints of negative incidents while flying, she wrote: “In recent years, we’ve placed a particular focus on giving our team members the tools and resources they need to properly handle and track customers’ mobility aids, and we’ve seen improvement in handling as a result.” One such effort, she said, was the introduction of wheelchair-specific bag tags on all flights; the tags can improve the tracking of mobility devices and make it more clear what the features of each device are.

Handling luggage

Mr. Brown goes to pick up his luggage, then finds out from an airport worker that the San Antonio airport doesn’t have any porter service available to help him carry his shower wheelchair, carry-on suitcase and two large checked bags to the car. The U.S. Department of Transportation requires airlines to assist disabled passengers with carrying their checked luggage if needed, but people with disabilities complain that, in practice, often either it isn’t provided or they can’t find someone to help them.

Erin Rodriguez, a spokeswoman with the San Antonio International Airport, said that all airlines provide assistance to people with wheelchairs, including helping with their luggage, at no charge. She added that the airport has phones throughout the terminal for travelers needing immediate or after-hours assistance.

The sun is setting, casting the sky pink beneath big, dark clouds as Mr. Brown maneuvers out of the cool airport into the humid Texas heat. (In the end, his travel companion helped him with his luggage; it would have posed a considerable challenge if he’d had to handle it on his own.)

At 7:38 p.m., he easily maneuvers up a ramp into a waiting car that, unlike the planes he just rode, is specially designed to accommodate his wheelchair.

In early July, Paralyzed Veterans of America filed a formal complaint against American Airlines on behalf of four members of its organization, including Charles Brown. Mr. Brown’s inclusion was based on his experience on the flights The Times documented in May. American Airlines did not immediately return request for comment regarding the complaint.