January 20, 1945 – “In view of 12th Army Groups’ recommendation that two L-4s in the Arty Air Sections of Army, Corps, Brigade, Division and Group HQs be replaced by L-5s as the latter are received as replacements, the comparative information below should be of interest.”
Advantages of the L-5 over the L-4 [true advantages in italics, others rather subjective]:
(a) Is more spacious and comfortable, therefore less fatiguing for pilot and observer.
(b) Has improved visibility.
(c) Has greater stability in rough air, therefore binoculars may be used.
(d) Has adjustable pilot’s seat.
(e) Has improved engine cowling fasteners.
(f) Has four moveable windows, therefore better ventilation.
(g) Has greater horsepower, therefore more payload, better maneuverability and more safety in take-offs.
(h) Is better for photo missions because of greater stability and width of unobstructed view.
(i) Can perform evasive maneuvers better because of higher climbing, top and diving speeds.
(j) Can operate from fields farther back from the front, or can go farther into enemy territory (dubious).
(k) Is less liable to damage on the ground from high winds.
Advantages of the L-4 over the L-5:
(a) Is easier to manhandle on the ground.
(b) Tire flotation is feasible in soft or rough landing field conditions.
(c) Tail cone ground clearance is greater, preventing damage when taxing over rough terrain.
(d) Wheel brakes are more adequate to aircraft weight and use in short fields.
(e) Shorter and less refined air strips are more accessible.
(f) L-5 ignition switch-magneto-ground circuit causes excessive electrical interference with 600 series radios.
(g) L-5 landing gear construction causes excessive fuselage damage when gear is damaged or strikes bad ruts.
(h) Carburetor heat more effective, without loss of engine power.
(i) L-5 oleo shock strut cylinders break after hard usage.
(j) L-5 generator shaft tends to wear (which requires more frequent maintenance inspections of accessory case).
(k) L-5 parking brake cannot be left on when aircraft is taxiing or left standing overnight due to deterioration of the rubber in the expander tubes.
(l) L-5 use of battery for radio, navigation and landing lights, and electric starter requires special care of electrical equipment.
(m) L-5 requires careful use of carburetor heat to prevent engine failures when icing or low temperature conditions prevail.
(n) Lower fuel consumption.
(o) Simplified field structural repairs without relying on higher echelon maintenance unit.
(p) Flexibility with fuels (L-5 demands 73 octane).
(q) L-5 has no cabin heater.
(r) L-5 requires more flying skill in short field flying.