| Sunshine Skyway Disaster |
I worked up a report on this event, highlighting the similarities and
differences with the Key Bridge disaster.
The chief difference was that the Baltimore incident happened in clear weather
and in a channel that was tangent (straight) from Fort McHenry all the way to
2 miles east of the bridge. So especially for an eastbound (outbound) ship
like Dali there are no channel bends even remotely near the bridge.
The Sunshine Skyway disaster was a perfect storm of multiple factors to the
point that the handling of the vessel cannot really be blamed, nor the design
of the bridge. Although these were very controversial at the time in the
aftermath.
The Sunshine Skyway disaster occurred on May 9, 1980, when the freighter
Summit Venture collided with the Sunshine Skyway Bridge in Tampa Bay, Florida,
causing a portion of the bridge to collapse. Here are the key facts and
findings.
Weather Conditions
- The collision happened during a severe thunderstorm with winds gusting up to
70 mph and zero visibility.
- Heavy rain and squall lines made navigation extremely challenging, obscuring
buoys and other visual aids.
- There was an about 90-degree change in wind direction (from SW to NW) during
the severe thunderstorm, which made navigation unpredictable and extremely
difficult.
- The ship's radar was rendered nearly useless in the dense rain, which
obscured both the channel markers and nearby hazards. No GPS tracking systems
back then.
Channel Design
- The shipping channel under the Sunshine Skyway Bridge was narrow and lacked
modern navigational aids.
- The bridge's piers were not adequately protected, leaving them vulnerable to
collisions.
- The channel included a 18-degree dogleg turn just a quarter-mile west of the
bridge. This abrupt turn added to the challenge of navigating eastbound
(inbound) large ships in poor weather. Local ship pilots called this the
"Combat Zone" due to the risks in passing the bridge and oncoming vessels
safely.
- After the disaster, the replacement bridge incorporated enhanced safety
features, including rock islands and dolphins (barriers designed to protect
bridge piers). [I have already opined on the impossibility of testing and
verifying this thru real-world tests.]
- The replacement bridge had a main span 1,200 feet long -- compared to 800
feet on the original which some mariners considered marginal for large ships.
- The replacement bridge main span was built about 1,000 feet east of the
original -- alleviating the closeness of the bridge to the channel 18-degree
dogleg.
- The Tampa Bay deep shipping channel is dredged and takes a number of bends
and doglegs between the Gulf and the terminals.
Impact and Aftermath
- The MV Summit Venture weighed about 19,000 tons and was moving at 8.5 knots
(9.5 mph).
- The Summit Venture was reportedly blown out of the channel due to strong
winds and low visibility, putting it dangerously close to the bridge's
unprotected piers.
- All of this unfolded at the worst possible moment — right as the ship
approached the bridge -- at 0.2 mile from the bridge visual and radar views
were obscured by the torrential rain.
- The collision caused the collapse of the southbound span of the bridge,
sending six cars, a truck, and a Greyhound bus plunging into the water.
- 35 people lost their lives, with only one survivor.
- The disaster led to the construction of a new Sunshine Skyway Bridge, which
opened in 1987 with improved safety measures.
Investigation and Findings and Legacy
- The NTSB (National Transportation Safety Board) determined that poor weather
forecasting played a role, as it did not provide adequate warnings about the
severity of the storm.
- The ship's pilot, John Lerro, faced both a pilot association investigation
and a court case. However, he was ultimately held blameless for the incident.
The court recognized that he had followed appropriate procedures to the best
of his ability under impossible circumstances. A perfect storm so to speak.
- John Lerro was unfairly castigated in the state and local press and by his
Tampa Bay piloting colleagues. The press mainly out of ignorance of the
technical issues at hand, which is par for the course for them, and his
piloting colleagues due to the fact that they saw him as an affirmative action
hire.
- John Lerro even after his exoneration, was still attacked by some in the
press, some in the piloting association, and some in the court system. It was
a dogs breakfast.
- This disaster highlighted flaws in bridge design, including the narrowness
of the main span (800 feet), the closeness to the channel dogleg, and the lack
of protection for the bridge piers.
- The new Sunshine Skyway Bridge built after the incident included dolphin
structures to shield the piers, had a longer main span of 1,200 feet, and was
relocated to a safer distance from a 18-degree dogleg in the shipping channel.
- The event also underscored the importance of advanced navigation aids and
improved weather forecasting for maritime safety.
The Summit Venture freighter was moving at approximately 8.5 knots (about 9.5
mph) when it collided with the Sunshine Skyway Bridge. While this speed might
seem relatively slow, the ship's massive size and weight of over 19,000 gross
tons meant that even at low speeds, the impact force was substantial enough to
cause the catastrophic collapse of the bridge's southbound span.
. . . . .
NTSB-MAR-81-3
National Transportation Safety Board
Marine Accident Report
Ramming of the Sunshine Skyway Bridge by the Liberian Bulk Carrier Summit
Venture, Tampa Bay, Florida, May 9, 1980
Quote:
The National Transportation Safety Board determines that the probable cause of
this accident was the SUMMIT VENTURE's unexpected encounter with severe
weather involving high winds and heavy rain associated with a line of intense
thunderstorms which overtook the vessel as it approached the Sunshine Skyway
Bridge, the failure of the National Weather Service to issue a severe weather
warning for mariners, and the failure of the pilot to abandon the transit when
visual and radar navigational references for the channel and the bridge were
lost in the heavy rain. Contributing to the loss of life and to the extensive
damage was the lack of a structural pier protection system which could have
absorbed some of the impact force or redirected the vessel. Contributing to
the loss of life was the lack of a motorist warning system which could have
warned the highway vehicle drivers of the danger ahead.
. . . . .
Separated out in bullet points --
The NTSB's probable cause for the Sunshine Skyway disaster identified several
key factors:
- The Summit Venture unexpectedly encountered intense thunderstorms with high
winds and heavy rain, which severely reduced visibility and made navigation
extremely difficult.
- The National Weather Service failed to issue a severe weather warning for
mariners, leaving the ship's crew unprepared for the sudden and extreme
conditions.
- The pilot lost both visual and radar references for the channel and the
bridge due to the heavy rain, which contributed to the ship veering off
course.
- The pilot did not abandon the transit despite losing critical navigational
references, which ultimately led to the collision.
[my opinion was that the loss of both visual and radar references occurred too
late and too close to the bridge. He didn't want to veer sharply back into the
channel because he knew that could cause a collision with a gasoline tanker
coming the opposite direction, very close but invisible in the storm.]
- The absence of a pier protection system to absorb or redirect the impact
contributed to the extensive damage to the bridge.
[my opinion on that has been posted before]
- The lack of a warning system for highway vehicles also contributed to the
loss of life, as drivers were unaware of the danger ahead.
Is "probable cause" an indecisive term?
The NTSB uses "probable cause" because investigations often face incomplete
evidence — wreckage may be lost, data corrupted, or witnesses unreliable.
"Probable" acknowledges this uncertainty while asserting the most likely cause
based on rigorous analysis. It’s a precise term, avoiding absolute certainty
when evidence isn’t conclusive, ensuring credibility and legal defensibility.
The NTSB's "probable cause" is not indecisive because it reflects a rigorous,
evidence-based conclusion drawn from extensive investigation, including data
analysis, witness interviews, and expert input. It identifies the most likely
reason for an accident, balancing precision with available evidence, and is
explicitly distinguished from speculative or inconclusive findings.
The legal defensibility may be the most important -- NTSB reports are for
determining accident causes for the issuance of safety recommendations to the
industry and government -- not intended to be used in a court of law to settle
any disputes about the accident.
_________________________________________________________________________________
Sources
DeYoung, Bill. Skyway: The True Story of Tampa Bay's Signature Bridge and
the Man Who Brought It Down. Gainesville: University Press of Florida,
2013.
NTSB accident report for the Sunshine Skyway disaster is titled "Marine
Accident Report: Ramming of the Sunshine Skyway Bridge by the Liberian Bulk
Carrier Summit Venture, Tampa Bay, Florida, May 9, 1980" (NTSB-MAR-81-3)
Creating the Sunshine Skyway Memorial, by Bill DeYoung
Roads to the Future articles:
Francis Scott Key Bridge (Outer Harbor
Crossing)
Baltimore Outer Harbor Crossing Replacement Proposal
Copyright © 2025 by Scott Kozel. All rights reserved. Reproduction, reuse, or distribution without permission is prohibited.
By Scott M. Kozel, Roads to the Future
(Created 9-6-2025, last update 9-6-2025)