In general, you can get good general dimensions from the Airplane Characteristics for Airport Planning documents (Boeing). These documents include the overall dimensions and everything relevant for the airport. This does not include the chord length though.
To get more accurate dimensions, you can download CAD drawings from Boeing. I did this for the 747-400 ...
Yes, a Boeing 747-830 exists.
There are a variety of codes for airplanes, one of the most common being the ICAO code. It lists the latest model of the 747 as B748.
However, Boing uses an additional, airline-specific code. The number 30 is given to Lufthansa and Condor, so the 747-8 in Lufthansa layout is the 747-830.
Until 2016 Boeing included customer codes into the aircraft model names. Your example 747-830 decodes as follows:
747: This is the general aircraft series.
-8: The 747-8 variant (in this case, a 747-8I, where I is for Intercontinental, the passenger variant).
30: The customer code for Lufthansa or Condor Flugdienst (see e.g. Wikipedia for a list of customer ...
No it cannot climb with only one engine.
If it can climb with one engine the plane would be a twin jet not a quad jet. The number of engines is determine by power require for normal operation plus a margin in case one engine malfunctions during climb out. An engine is a very expensive piece of equipment both in term of up front cost and maintenance so two ...
I thought we could just check the thrust and weight, but it's not that easy. The static thrust of one engine looks like it is enough for both aircraft:
B744 has MTOW 4050 kN, estimating L/D to 18 it needs 225 kN to maintain altitude and the static thrust is 276–282 kN (depending on engine option).
A388 has MTOW 5640 kN, using the same L/D it needs 313 kN to ...