Crash investigators are still waiting to retrieve the Cessna 152 aircraft and police have said it could be months before the cause of the crash is known.
But now it has emerged Space Coast Aviation, based on Merritt Island, is currently under investigation over another crash last August which left a young Irish woman in hospital.
Student pilot Carly Beattie, 21, and her 24-year-old brother Daniel, both from Penicuik, died when their rented plane plunged into thick woodland near Florida's Blue Cypress Lake at the end of last week.
The plane was being flown by Ms Beattie, who friends said had always dreamed of being a pilot.
Police have told how rescue teams had to fight through alligator-infested swamps to recover the bodies of the Lothians siblings.
It is understood the 18-strong squad braved snakes and deep mud to wade to the wreckage on Friday evening.
The rescuers were said to be "highly emotional" when they recovered the remains, having walked through the deadly terrain for a mile. They had to spend a whole day there as they worked out how to remove the bodies.
After the crash, several planes were sent up to look for the wreckage, but it was only when a signal from one of the Beatties' mobile phones was traced that they were able to refine the hunt.
A distress signal had been sent from the aircraft just before it nosedived.
Deputy James Harpring, of the Indian River County sheriff's office, reportedly said: "A specialist helicopter with a lift was unable to reach the crash site and in the end we had to hand-carry the remains.
"There was nothing else for it. The whole area is very densely wooded and teeming with dangerous creatures like rattlesnakes and water moccasins, alligators and even wild boar.
"On top of that, the mud is almost chest-deep in places.
"The plane came down slightly more than three-quarters of a mile from the nearest road and even that is an unmade dirt track.
"It was also very emotional.
"Even though we deal with injury and loss of life all the time, it is highly unusual to have to hand-carry remains.
"Out of respect for the family, I don't want to describe the bodies but they bore the sort of injuries you would expect in a crash of this kind.
"Sadly, it could now be some time before we know the cause of the crash as investigations can take months to complete."
The siblings are the children of 54-year-old retired pharmacist Tom Beattie and wife Elaine. They were on holiday with Daniel in Florida. Carly was living in the US as part of her training to become a professional pilot.
Over the weekend, a woman at the family home said the family were "utterly devastated".