Philippine Bangka Outrigger and Boom Variations

The bangka -- also known as banca and paraw -- is a double-outrigger boat ubiquitous in the Philippines. According to one online dictionary of Tagalog (an Austronesian language, one of the more commonly spoken languages of the Philippines), the word bangka simply means "boat," and this appears to be accurate and logical, given the great diversity in bangka configurations.

Indeed, there seem to be only two or three common features of bangkas: their main hulls are always narrow; they are always double-ended; and they almost always have two outriggers. Their differences, however, are manifold, including variations in materials, construction methods, most aspects of hull shape, houses, internal arrangements, overall size, propulsion, decoration, and usage. They're sometimes called the "Jeeps of the sea" because they are supposed to be able to do everything, but they do everything not necessarily because they are versatile, per se, but because there's a different style of bangka for nearly every possible application. 

We've written about bangkas several times already, but an offer of photos from reader Michael Williams of Flatwolf Photography has given us a good reason to look at them yet again. What strikes us most about the current batch of images is the variation in the configuration of outrigger booms. As always, click any image to enlarge.

We'll begin with this image of a medium-size power bangka as a kind of baseline for comparison. The outrigger float -- a single bamboo pole of large diameter -- angles fairly steeply up toward the bow. To achieve this, forward boom slopes down quite gently, while the aft boom takes an abrupt turn downward. One finds these two boom configurations in different combinations on different bangkas.

Three booms with progressively steep ends to accommodate the sloping floats. The booms are stout and rectangular in section. Round poles lashed atop them do not seem to add much, if any, strength.

The boom in this small paddling bangka is fastened with lashings to a cleat that spans between two frames about halfway between the gunwales and the bottom of the interior. The frames themselves extend above the gunwales, providing stops that prevent the boom-and-float assembly from shifting forward or aft.

The booms to the right and left of the image are straight across the middle, while the boom in the middle is bent down somewhat amidship, for a bit of a gull-wing configuration. The booms appear to be built up of three sections, the joints visible where the horizontal section transitions to a downward curve toward the float. The joints are probably simple scarf joints, lashed with cordage and covered with some kind of sealant or adhesive. 

These light, obviously very flexible booms in this nicely finished, small power bangka appear to be in one piece, although they might be scarfed together as in the previous photo but finished more carefully. The booms are placed outboard of the extended frame tops. In comparison, the booms on the boat in the third photo were placed inboard the extended frame tops.

The five booms on this large passenger bangka are complex structures. Amidships, each appears to be an open-topped, box-section girder from which a tapered, rectangular-section beam protrudes outboard with a slight downward slope. Lashed on top of these are several bamboo poles, lashed together and extending further outboard. One pole in this bundle extends even further outboard and curves downward to contact the float, which is itself a few bamboo poles of small diameter, providing probably only modest buoyancy. In the main, the booms appear to be quite rigid, although the lightness of the final outboard section may impart some flexibility.

A single-outrigger bangka. This appears to be by design, and not a partially disassembled boat. The float is a carved piece of timber, not a bamboo pole as in most other examples. The amount of flexibility in the construction appears to be minimal.

The outriggers on this small paddling bangka tilt downward toward the bow. We can't think of a good reason for this unusual design feature.