Kaboom!
Why did Della Duck take the Spear of Selene?
Here is a link to a site discussing fan theories.
https://drummergirl231-2.tumblr.com/post/180762934980/what-if-della-meant-to-crash
And one theory is that Della knew the Spear of Selene was sabotaged and about to explode and took off in it to save every one from an explosion that would destroy half of Duckburg.
But in real life if a rocket as powerful as the Spear of Selene exploded it wouldn't destroy HALF of a city like Duckburg.
Repeat, in real life if a rocket as powerful as the Spear of Selene exploded it wouldn't destroy HALF of a city like Duckburg.
There have been many real life explosions of large rockets on the launch pad, such as the Nedelin catastrophe 24 October 1960, the Intelsat 708 crash 15 February 1996, the 1980 Plesetsk launch pad disaster 18 March 1980, and the 1980 Damascus Titan missile explosion 19 September 1980.
And of course the explosion of the N-1 test rocket just after launch on July 3, 1969 that destroyed the launch complex and was one of the largest artificial non nuclear explosions ever - despite the fact that the majority, perhaps up to 85 percent, of the propellant aboard did not detonate.
The N-1 explosion is estimated to have equaled a kiloton of TNT, as compared to the 21 kilotons of Fat Man at Nagasaki or the 15 kilotons of Little Boy at Hiroshima. The 1 kiloton explosion of the N-1 rocket was 50 to 100 times the estimated 10 to 20 ton yield of the Mk-54 warhead of the Davy Crocket weapon system, which is about the minimum possible yield of a nuclear bomb.
Duckburg may be a large city, but it probably doesn't cover anywhere near as much ground as London, New York, Tokyo, or other major metropolises. So I don't think that an explosion of the Spear of Selene would have destroyed HALF of Duckburg.
And of course it is always possible that Scrooge would have been sensible enough to build his rocket launch complex miles away from the nearest community to avoid massive casualties in any explosion, as real life people do.
Anyway, by the time this is read we may know the reason why Della took the Spear of Selene.