Going Solar Seawind Style
Going Solar Seawind Style
Have you ever thought about what it takes to design and then implement a heating and cooling system from scratch in a first-ever experimental airplane? I have. The first obstacle is that the standard heat source. The engine, is about twenty feet – as ducts run – from the cockpit. How would you move super hot jet engine air, cool it to cabin comfortable Temps. Furthermore, how would you distribute it to pilots and passengers? Since I chose a non-standard engine, a PT6, the Seawind kit manufacturer, Seawind North America, SNA, understandably offered no help. Even if it could be designed how could it be controlled so that it doesn’t bake the flight crew and passengers in the summer and send them shivering in the winter? The answer may surprise you.
Think Solar Power:
First, I had this amazing dream. I just had to write it down: “Before you move inside a box, first step outside.” I found that people who do this really appreciate fine design and engineering. So I stepped out and I asked an even larger question: Why rely solely on the engine when a colossal heat source is right over our heads? Moreover, when admirers comment that N71RJ is all glass I sometimes think they’re referring to the 270 degrees of Plexiglas surrounding the entire cabin and not the G900 suite itself. It’s like a solarium.
Will solar power work in the cold Northeast? This design feature, unique to Seawind amphibians, provides solar warmth even on the coldest sunny days! To test this, one cold New England winter day I closed the canopy and watched the thermometer shoot from 20F to a warm 77F in just minutes. What’s even more amazing, I found, is while flying in class A airspace where the outside Temps are arctic-like, the cabin stays comfortably warm mostly from, yes, you guessed it, solar power. I recently heard someone say: “You can feel completely comfortable flying a Seawind.” But what if there’s no sun? Ah, I just knew you’d ask!
PT6 power gets N71RJ on top.
With 550 HP driving an MT five-blade propeller, the much lighter N71RJ slices through clouds like a Pilatus to level off up to 24,000’. Most often on the way up the sun pops out well below this service ceiling. Here the sun now becomes the primary heat source. Moreover, at these flight levels a glance at the G900X shows about 200 TAS. You’re now humming along in the sun, eating terrain and conserving precious fuel. Also, like just about every other system on N71RJ, the solar system is backed up by a HVAC system I designed that keeps the cabin cozy.
It varies and blends cold inlet air and hot engine-supplied air to supplement solar power and keep you comfy even at night. Furthermore, this engine HVAC system is bolstered by cabin fresh air vents that also cool you if there’s too much sun or cabin heat. That’s great for summer flying – especially to your secret lake retreat, swimming or fishing hole. Activate the Trutrak auto pilot and before you know it, you’re there! Maybe you haven’t flown a Seawind amphibian yet. Imagine being warmed by the sun at altitude. You’ll find you won’t need a beach chair upon arrival. What makes solar work so well for this unique jet-prop configuration?
Staying warm at 19,000 feet. The secret is the canopy sealing. Wherever cold air could sneak in it’s stopped cold by an airtight gasket. With the canopy sealed it takes far less solar power to warm your cabin. Think about it; whether you currently benefit from solar or not it’s a good idea to make your cockpit as airtight as possible to conserve your heat. It’s especially important should you have an HVAC failure.
A tight cabin will give you some added precious time to descent, save the day and you won’t have to thaw out any passengers. Going solar means thinking beyond rooftop panels, it also applies to flying today – keeping you warm and sunny – courtesy of your very oldest heat source.
Sealed canopy. Notice the sun roof, aka safety hatch. See more photos at https://abpic.co.uk/pictures/model/Seawind%203000
