England's top hospital inspector has warned that the NHS is standing "on a burning platform," with most trusts needing to improve patient safety.
The analogy came as Professor Sir Mike Richards, the Care Quality Commission's chief inspector, revealed that four out of five trusts are lacking in that area.
Safety remains an area of "real concern," Sir Mike said, having completed a first round of new inspections at UK hospitals.
Sir Mike also claimed the NHS's model of acute hospital care must be modernised.
He cautioned that what once worked well for the health service "cannot continue to meet the needs of today's population".
Among Sir Mike's findings were a "wide variation in quality" between hospitals and between services - sometimes even within the same building.
The inspections, which covered 136 acute non-specialist trusts and all 18 specialist trusts, discovered pockets of "very poor quality care" in good hospitals.
Rising demand for care coupled with economic pressures were found to be creating "difficult-to-manage situations that are putting patient care at risk."
The CQC's State of Hospitals report said: "The safety of hospitals remains our biggest concern, with four out of five trusts needing to improve."
Sir Mike also warned of a "failure to learn" when things go wrong.
None of the hospital trusts received an outstanding score for safety, while 81% of the non-specialist trusts were deemed inadequate or requiring improvement.
More than half of specialist trusts were rated as requiring improvement in terms of safety.
Some 11% of hospital trusts were even given the lowest rating in this area.
Meanwhile, across 199 urgent and emergency services inspected, 7% were deemed to be inadequate.
In total, emergency services had more ratings of improvement required than good or outstanding.
The report said: "We are also concerned that some may be over-reliant on their reputation and not assuring themselves of the quality of care they are delivering."
Sir Mike said he had found "high levels" of compassionate care in "virtually every hospital."
He added: "We have witnessed some fantastic care and examples of innovative practice, but we have also found a wide variation in quality both between hospitals and between services within the same hospital.
"Safety remains a real concern, often due to a failure to learn when things go wrong."
An NHS England spokesperson said the report was right to argue for more profound changes being planned for acute hospital care.
Jonathan Ashworth, shadow health secretary, said: "The CQC’s stark warning that our NHS stands on a ‘burning platform’ must be at the forefront of the Chancellor’s priorities ahead of next week’s Budget.
“Our hardworking and stretched NHS staff cannot be expected to pick up the pieces from this Government’s failure to properly fund our NHS and social care system."