Succession Intrigue from and upon Venezuelan Leader

President Hugo Chavez of Venezuela has just claimed his navy chased a foreign nuclear submarine away from Venezuela’s island of La Orchila north of Caracas.

1- How would Hugo's navy detect a nuclear submarine that wanted to remained undetected (submerged)?
2- If a foreign vessel was actually spotted on the surface, what excuse could Venezuela's military commander, conducting training drills near the island at the time, possibly offer for allowing it to escape? The ANSWER:

“It was pursued. It escaped because it’s much faster than ours. The speed and size of the foreign submarine indicated “it’s a nuclear-powered submarine,” Chavez said.

3- Assuming the fast vessel really was a submarine, why conduct ISR (Intelligence, Surveillance, and Reconnaissance) on the surface? If not ISR, why conduct insertion on the surface? CONCLUSION: Not a submarine.
4- What kind of vessel was spotted? Possible ANSWER: A go fast boat smuggling drugs.
(they can out run most subs), and William Brownfield, U.S. assistant secretary of State for international narcotics and law enforcement, recently said illegal drugs trafficking through Venezuela were at an “explosive” rate.
5- According to former U.S. Assistant Secretary of State Roger Noriega in a recent column for the InterAmerican Security Watch, Chavez’s cancer is spreading more quickly than expected and could kill him within six months.
6- In 2008 the US Department of the Treasury asked for Henry Rangel Silva's US accounts to be frozen on the charge that he had helped the FARC in narcotraffic activities. In November 2010, Rangel Silva declared that the military forces are "married to the political, socialist project" lead by Hugo Chávez in Venezuela. Shortly after that, Chávez promoted Rangel to General-in-Chief.

Reading between the lines above...
Chavez has apparently discredited Venezuela's military commander, Henry Rangel Silva in advance of the expected transition in Venezuela's top leadership. This is particularly noteworthy because Rangel Silva had taken part in Venezuela's 1992 military coup with Hugo Chavez and rose to power by expressing public confidence in Chavez, and only after the U.S. attempt to freeze his US accounts.

Meanwhile, Delegate to Venezuela’s National Assembly William Farinas implied for the public's consumption that the foreign submarine was another sign that a [foreign] “empire” [read "US"] sought to control Venezuela’s oil industry.

Has Rangel Silva been up to mischief with a foreign power? Is he hiding involvement in drug trafficking? Is he being supported by a foreign power to take over when Chavez goes naturally?

Submarines are always silent and strange.