That makes much more sense

[mdlbear]

According to this NY Times article, the liquid explosive planned in the British plot was HMTD.

A chemist involved in that part of the inquiry, who spoke on the condition of anonymity because he was sworn to confidentiality, said HMTD, which can be prepared by combining hydrogen peroxide with other chemicals, "in theory is dangerous," but whether the suspects "had the brights to pull it off remains to be seen."

While officials and experts familiar with the case say the investigation points to a serious and determined group of plotters, they add that questions about the immediacy and difficulty of the suspected bombing plot cast doubt on the accuracy of some of the public statements made at the time.

"In retrospect," said Michael A. Sheehan, the former deputy commissioner of counterterrorism in the New York Police Department, "there may have been too much hyperventilating going on."

Some of the suspects came to the attention of Scotland Yard more than a year ago, shortly after four suicide bombers attacked three subwav trains and a double-decker bus in Londo~ on July 7, 2005, a coordinated attack that killed 56 people and wounded more than 700. The investigation was dubbed "Operation Overt."

(from cryptome)

Comments

[ravan.livejournal.com]

Still not viable in the scenario:

XX grams of hexamethylenetetramine is dissolved in YY g of 30% hydrogen peroxide and stirred mechanically at 0 degrees. ZZ grams of powdered citric acid is slowly added with continued stirring. The mixture is stirred for 3 hours at 0 degrees and then allowed to warm to room temperature and stand for 2 hours. The white crystalline product is filtered off, thoroughly washed with water, rinsed with methanol, and air dried. If more than double the recommended amount is made at once, the product will decompose exothermally while the solution warms. HMTD may be stored under water with no explosion risk and no increase in the rate of decomposition. - http://www.sciencemadness.org/library/HMTD_structure.html

The stuff takes 5 hours to make, plus time to filter off the precipitate and dry. The combined ingredients must be stirred in an ice bath for 3 hours, then let stand at rt for two more.

Now, if they made it and stored it in a bottle of water (although I'd wonder about the crystals at the bottom), it would be stable until they dried it. But they'd still have to filter it and dry it on the plane.

I'm really surprised they hadn't blown up their apartment.