At least 5 to 6 days in advance, make figure piped pieces using royal icing.
For firefighter in front holding hose: Place waxed paper over pattern and use tip 2A to pipe body and head. Cut a 2 in. length of drinking straw and insert in shoulder to form arm, leaving 1 1/4 in. exposed. Use tip 9 to pipe arm over straw; let dry. (Note: Make sure to keep straw opening free of icing for inserting wires later.)
For firefighter in back: Place waxed paper over pattern and use tip 2A to pipe body and head. Pipe tip 9 arm (do not insert straw); let dry 1 day. When completely dry, turn over and repeat same process on backside for each firefighter. Immediately insert lollipop stick in boots for cake support, leaving 2 in. exposed; let dry.
When both firefighters are completely dry, pipe tip 12 helmet and form front and back bills with finger dipped in cornstarch. Pipe tip 12 ball on top of head and form into dome shape. Pipe tip 3 shield on front of hat (smooth with finger dipped in cornstarch). Pipe tip 3 lines and button on top of helmet. Pipe tip 3 hair, tip 2 eyes and nose, tip 1 mouth.
For ladder: Place waxed paper over pattern and pipe with tip 5; let dry. For water drops from hose: Cut 4 white cloth-covered wire to 6 in. lengths; pipe tip 3 bead drops on wire; let dry. Wrap wires together with white florist´s tape, 1 in. at bottom. Set aside.
For wheels: Cover pattern with waxed paper and pipe tip 12 circular motion wheels. Pipe tip 12 dot centers (smooth with finger dipped in cornstarch).
For nozzle: Tint 4 oz. fondant gray. Break off a 5/8 in. piece of fondant for cone. Dust inside of tip 9 with cornstarch and insert in gray fondant to form cone. While fondant is in tip, insert wooden skewer to form hole on tip of nozzle to accommodate wired water spray; remove.
Roll a 1/8 in. thick diameter log and wrap around nozzle and attach with damp brush; let dry. When completely dry, attach nozzle to front firefighter with icing; pipe tip 3 hands.
For fire truck, bake and cool pound cake in loaf pan. Trim cake to 6 1/2 in. x 3 in. Ice cake smooth, use toothpick to mark 1 1/4 in. x 1 in. side windows and 2 in. x 1 in. front window. Outline and pipe in windows with tip 3 (smooth with finger dipped in cornstarch).
Outline windows with tip 3 and add tip 3 zigzag trim and details on sides.
Bake and cool 2-layer (4 in. high) 6 in. cake; 2-layer (make each layer 1 1/2 in. to cake 3 in. high cake) 8 and 10 in. cakes. Ice all cakes smooth.
Pipe tip 18 top and tip 21 bottom shell borders on 8 and 10 in. cakes. Divide 6 in. cake into 8ths. Pipe tip 16 yellow zigzag garland (1 in. deep) between division marks. Pipe tip 3 red drop string garland above yellow; add tip 3 green dots at each division point.
Pipe tip 16 top and tip 18 bottom shell borders on 6 in. cake. Print tip 5 message on cake sides. Position cakes on stands. Position truck, hydrant candle and firefighters on cakes. Insert wired water spray into hose nozzle. Roll a 1/4 in. gray fondant log hose, approximately 14 in. long and attach to hydrant with icing; drape over back firefigher and attach under arm and trim.
Roll a second log, approximately 6 in. long and attach under side of front firefighter arms by nozzle and draping over back firefighter to attach. Position candles.