A-1 Husky
Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 300; Flight Crew Total 3800; Flight Crew Type 250
Other / Unknown; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
General None Reported / Taken
Aircraft
On the initial climb out on the MRY5 departure; we had some trouble maintaining a decent climb rate once entering IMC. Although we know the aircraft meets the departure minimums; the aircraft has been modified with a composite prop and amphibious floats. These floats in particular drastically reduce the climb performance of the aircraft.We requested the MRY departure off 28L because we knew we would not meet the opposing (active traffic) runway requirements. However; once departing; we received a low altitude alert from the air traffic controller. At this time; we were very carefully monitoring our AGL and terrain using multiple onboard GPS and navigational systems. However; we apparently went below the trigger altitude for the controller. We are not sure if we actually were below the departure minimums at that point; but were close enough to require a warning. We continued climbing over the water on the departure; and were able to break out of the marine layer shortly thereafter. One thing that I would like to see; is better performance data published for the aircraft; but we are aware that being a seaplane we are limited. In the future; perhaps we will opt to navigate using a different technique; perhaps depart Special VFR and remain in Class G airspace once departing the airport. This is our normal course of action; and the reason I stay off whore whenever ferrying seaplanes.
Aviat Husky pilot reported receiving a low altitude alert from ATC during climbout.